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Antenatal interventions for reducing weight in obese women

for improving pregnancy outcome (Review)

Furber CM, McGowan L, Bower P, Kontopantelis E, Quenby S, Lavender T

This is a reprint of a Cochrane review, prepared and maintained by The Cochrane Collaboration and published in The Cochrane Library 2013, Issue 1

http://www.thecochranelibrary.com

Antenatal interventions for reducing weight in obese women for improving pregnancy outcome (Review)

Copyright © 2013 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.

http://www.thecochranelibrary.com/http://www.thecochranelibrary.com/


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T A B L E O F C O N T E N T S

1HEADER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1 ABSTRACT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2PLAIN LANGUAGE SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2BACKGROUND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5OBJECTIVES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6METHODS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7RESULTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7DISCUSSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7 AUTHORS’ CONCLUSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8 ACKNOWLEDGEMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

14CHARACTERISTICS OF STUDIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

23DATA AND ANALYSES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

23 APPENDICES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

26CONTRIBUTIONS OF AUTHORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

26DECLARATIONS OF INTEREST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

27SOURCES OF SUPPORT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

27DIFFERENCES BETWEEN PROTOCOL AND REVIEW . . . . . . . . . . . . . . . . . . . . .27INDEX TERMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Authors’ conclusions

There are no trials designed to reduce weight in obese pregnant women. Until the safety of weight loss in obese pregnant women

can be established, there can be no practice recommendations for these women to intentionally lose weight during the pregnancy

period. Further study is required to explore the potential benefits, or harm, of weight loss in pregnancy when obese before weight loss

interventions in pregnancy can be designed. Qualitative research is also required to explore dietary habits of obese pregnant women,

especially those who are morbidly obese.

P L A I N L A N G U A G E S U M M A R Y

Trials of interventions for pregnant women who are obese to lose weight and improve pregnancy outcomes.

Pregnant women who are obese risk serious complications for themselves and their children. The mother is more likely to develop

diabetes or high blood pressure or pre-eclampsia during pregnancy, and the pregnancy may end in a miscarriage or stillbirth. The baby

could have serious anomalies at birth, including spina bifida, cardiovascular anomalies, cleft lip and palate, or limb reduction anomalies.

Some obese women have premature births. At birth, the labour may be longer and other complications can lead to a caesarean birth.

The baby may also be bigger at birth than is normal, and there is evidence that the children of obese mothers go on to be obese. The

advice for obese women in managing their weight during pregnancy is that weight loss should be avoided, and weight gain should bebetween 5.0 and 9.1 kg. Yet observational studies of large numbers of pregnant women indicate that some obese women, especially

those who are heavier, lose weight during pregnancy. We do not have any clear results that indicate that losing weight when pregnant

is safe for a mother who is obese, or for her baby. This Cochrane review aimed to evaluate trials that were designed for obese pregnant

women to lose weight. No randomised controlled trials were found. We recommend that further research is conducted to evaluate the

safety of interventions for weight loss when a woman is pregnant and obese for the mother and her baby.

B A C K G R O U N D

Description of the condition

Obesity is defined as ’abnormal or excessive fat accumulation that

mayimpairhealth’( World HealthOrganization 2006). Thepreva-

lence of obesity is now at epidemic proportions, and is one of the

most important challenges of the 21st century.

Body mass index (BMI) is commonly used to measure an in-

dividual’s weight in relation to their height. It is expressed as

body weight (kg) divided by the square of height (m²). A cal-

culation of 18.5 to 24.9 (kg/m²) is desirable (normal weight),

whereas 25 to 29.9 (kg/m²) is ’overweight’, 30 (kg/m²) or above is

’obese’ (Zaninotto2006). The World Health Organization( WorldHealth Organization 2000) has further classified obesity as:

• BMI 30 to 34.9 (kg/m²) - class I obesity;

• BMI 35.0 to 39.9 (kg/m²) - class II or severe obesity;

• BMI 40 (kg/m²) and above - class III or morbid obesity.

The risks related to being obese at the start of pregnancy are sub-

stantial, and may involve the pregnancy, birth, and later life for

both the woman and her infant.

Risks in pregnancy for obese women

Compared to normal-weight women, obese women are more at

risk of pregnancies affected by congenital anomalies, including

spina bifida, cardiovascular anomalies, cleft lip and palate, and

limb reduction anomalies (Rankin 2010; Stothard 2009). Still-

birth is also more common (Chu 2007; Flenady 2011; Ovesen

2011) and there is a possibility that miscarriage is more likely

in obese women (Metwally 2008). Several studies suggest that

gestational diabetes, hypertension, and pre-eclampsia/eclampsia

are common pregnancy complications when obese (Baeton 2001;

Doherty 2006; Ovesen 2011; Sebire 2001). Also, around one-fifth

of women who are obese at the start of the pregnancy give birth to

large (macrosomic) babies (defined as greater than 4000 g or larger

than 90th

centile) (Baeton 2001; Sebire 2001; Zhang 2007).

Risks during birth for obese women

The pregnancies of obese women are longer, and prolonged ges-

tation may lead to complications at birth. Data from the Dan-

ish Birth cohort from 1996 to 2004 indicate that post-term birth

(pregnancy length longer than 294 days) is correlated with higher

pre-pregnancy BMI Oleson 2006. In clinical practice, prolonged

2Antenatal interventions for reducing weight in obese women for improving pregnancy outcome (Review)



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pregnancies are more likely to be induced (Doherty 2008), and

inductions may be unsuccessful when obese (Kerrigan 2009).

Caesarean births are more frequent in women who are obese.

Heslehurst 2008 carried out a systematic review of the impact of

BMI on pregnancy outcomes. The results indicate significantly

reduced odds for vaginal birth when overweight, and obese. Theseresults are corroborated with the analysis of Danish births from

2004 to 2010 as those obese, andmorbidly obese, were more likely

to give birth by planned or emergency caesarean section (Ovesen

2011). Operative birth assistance is needed more often for delays

in labour when obese and compared with normal-weight women

(Kerrigan 2009; Zhang2007). Fetaldistressin labourhas also been

reported as morelikely, anda reason for emergencycaesarean birth,

in this group of women (Doherty 2006). In addition, caesarean

births maynot alwaysbe straightforward as complications of failed

epidural and spinal anaesthesia are more common in those who

are morbidly obese (Knight 2010).

Risks after birth for obese women

Complications after birth are more likely for obese women. An

increase in the incidence of postpartum haemorrhage and infec-

tions (including wound, urinary tract, perineum, chest and breast)

have been reported in obese women,when compared with normal-

weight women (Heslehurst 2008). Furthermore, excessive weight

gained during pregnancy in women who are already obese is likely

to be retained after the birth Rooney 2005, and may lead to health

complications such as diabetes andheart disease in later life (Linne

2003).

Risks to the neonate when the mother is obese

The neonates of obese women are at increased risk of increased

morbidity and mortality compared with babies born to normal-

weight women. Preterm birth is also more likely, and the time

to commence spontaneous respiration immediately after birth is

longer, more resuscitation is required, and there is more risk of

neonatal hypoglycaemia, in babies of obese women (Heslehurst

2008). Furthermore, the children of mothers who are obese at the

start of their pregnancy are likely to be overweight at the age of

three years (Olson 2009). A population-based case-control cohort

study of children aged between two and five years diagnosed with

autism spectrum disorder and developmental delays in California

2003 to 2010 indicates that maternal obesity in pregnancy may

be a risk factor for developmental delays in later life (Krakowiak

2012). Heavier women (those morbidly obese) are also more likely

to have increased risks of poor outcomes for the infant across the

childbearing continuum (Knight 2010).

Weight management for obese women in pregnancy

There is little robust evidence about optimal weight management

in pregnancy for obese women. Pregnancy weight varies between

individual women (Carmichael 1997), isnot linear(Dawes 1991),

and is related to variables such as maternal age, pre-pregnancy

body size, parity, smoking, ethnicity, hypertension, and diabetes

( Abrams 1995; Chu 2009).

Guidance on weight gain in pregnancy across all maternal weights

is contentious. Over the last 20 years, guidance for clinical staff on weight management in pregnancy has been based on recom-

mendations from the US Institute of Medicine (Medicine 1990).

These guidelines have been controversial as they were based on

research studies that lacked sufficient rigour to be scientifically

sound. These guidelines were based on population-based obser-

vational studies ( Johnson 1995), and studies that did not account

for other confounding variables (Feig 1998). In 2009, the US In-

stitute of Medicine Guidelines were revised, and the new guid-

ance based on a wider review of maternal and fetal outcomes (fe-

tal size, risk of unplanned caesarean birth, and excessive postpar-

tum weight retention) (Rasmussen 2009a ). Early guidance recom-

mended that obese pregnant women should gain a minimum of 7

kg (Medicine 1990), but in 2009, it was recommended that obesepregnant women should limit their weight gain to between 5.0 kg

and 9.1 kg (Rasmussen 2009b).

Weight loss in obese women in pregnancy

Several observational studies suggest that some obese pregnant

women gain minimal weight in pregnancy, and even lose weight.

A retrospective review of pregnancy outcomes in the US found

that 11% of obese women lost weight, or maintained their weight,

compared to 0.1% of normal-weight women (Edwards 1996).

Bianco 1998 reviewed the outcomes of pregnant women with a

BMI greater than 35 and found that 9% lost weight, or gained no

weight, compared to 0.2% of normal-weight women. Two morerecent studies show similar results. Data from 136,802 women

giving birth to singleton fetuses between 1996 and 2001 across

21 states in the US indicated that low weight gain (less than 0.12

kg/wk) was more common in those obese (8.3%, n = 1315) and

morbidly obese (19%, n = 1287),than those normalweight (1.9%,

n = 1780) (Dietz 2006). Rode 2007 analysed data from 2248

Danish women of all weights at 37 weeks of gestation and found

that 9.7% (n = 15) of obese women (n = 155) gained less than

1 kg at this stage of their pregnancy. Another study reviewing

gestational weight gain and the riskof adverse pregnancy outcomes

reported that 12 of 328 obese women in the total sample of 2011

women lost weight, compared to only one woman in each of the

normal weight (n = 1227) and overweight (n = 456) groups (Oken

2009), although these differences were not significant.

More recently, published studies exploring gestational weight gain

suggest that incidence of weight loss in pregnancy increases as

women’s weight increases; Bodnar 2010, Hinkle 2010, Beyerlein

2011 and Blomberg 2011 found that weight loss in pregnancy was

more likely in morbidly obese women.

Itis importantto note that some women deliberatelylose weightin




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pregnancy. Bish 2009 and Cohen 2009 both reported around 8%

of pregnant women of all weights attempting to lose weight using

strategies such as limiting calories and fat intake, and increasing

exercise. When their data were analysed according to BMI cate-

gory, the proportions increased to almost 13% of obese women

attempting weight loss in pregnancy (Bish 2009; Cohen 2009).

Risks associated with weight loss in obese women

during pregnancy

The current evidence related to weight loss and obstetric and

neonatal outcomes in all pregnant women is limited.

Maternal dieting and restricting food intake in the first trimester

of pregnancy may be associated with increased risk of the fetus

developing a neural tube defect (Carmichael 2003). Prolonged pe-

riods of fasting (greater than 13 hours) and not eating are also

linked to preterm birth and increased maternal corticotropin-re-

leasing hormone concentrations (Herrmann 2001). Furthermore,

extreme weight loss (greater than 15% of pre-pregnancy weight)in pregnant women suffering from hyperemesis gravidarum is as-

sociated with hospitalisation and the need for parenteral nutrition

(Fejzo 2009). These women suffered symptoms including gall-

bladder and liver dysfunction, renal failure and retinal haemor-

rhage (Fejzo 2009).

Low maternal weight gain and weight loss in pregnancy have been

associated with restrictions in fetal growth. Important evidence

is available from Holland during the winter of 1944/1945, when

food was severely limited because of a harsh winter and an em-

bargo on food transportation. Many pregnant women at the time

had food intakes of less than 1000 kcal/daily for a period of seven

months. Analysis of birth records from this period in the west-

ern Netherlands indicate that birthweight, crown-heel length, andhead circumference decreased after exposure to famine in the third

trimester (Stein 2004). An analysis of maternal weight in preg-

nancy from women based in Amsterdam who gave birth between

August 1944 and April 1946 enabled comparisons of birth param-

eters immediately before famine, during food restriction, and after

liberation. Maternal weight loss and weight gain below 0.5 kg/

week were associated with reduced birthweight, length and pon-

deral indices (Stein 1995).

Some studies associate maternal weight loss with risks of preterm

birth, small-for-gestational-age infants, and some neonatal com-

plications. Edwards 1996 found that obese women who lost

weight, or gained nothing in pregnancy, were significantly more

likely to give birth to smaller infants with birthweight less than

3000 g and be small-for-gestational age compared with obese

women who gained pregnancy weight within 1990 guidelines

(Medicine 1990). Furthermore, a systematic review suggested that

restricting protein/energy intake in overweight pregnant women,

or women who were gaining weight excessively, may harm the fe-

tus (Kramer 2003). Dewey 1994 proposed that low energy intakes

in pregnancy may result in ketosis that can affect the fetus.

Other studies indicate that weight loss or gaining no weight when

obese may be beneficial. Bianco 1998 found that the incidence

of low birthweight and small-for-gestational-age births were not

increased in women with BMI greater than 35 who either lost

weight, or gained nothing, during pregnancy.

Emerging evidence from retrospective cohort studies suggests that weight loss in pregnancy for obese women may have substantial

benefitsforboththemotherandinfant.Oken 2009 reviewed 2011

mother-child pairs in the US against five adverse outcomes related

to gestational weight gain: preterm birth, small-for-gestational-

age infant, large-for-gestational-age infant, substantial maternal

postpartum weight retention, and child obesity at age of three

years. The results indicated that the lowest predicted prevalence

of all five adverse outcomes occurred with a weight loss of 0.19

kg/week for obese women, which equates to a total loss of 7.6

kg for obese women over all of the pregnancy ( Oken 2009).

Beyerlein 2011 reviewed 709,575 births in Bavaria from 2000 to

2007 and stratified the data according to BMI category. Small

weight losses of up to 5 kg were associated with lower risks forpre-eclampsia in obese class II women and non-elective caesarean

section in obese class 1 women (Beyerlein 2011). Less large-for-

gestational-age births were also reported for obese class I women,

but an increase in small-for-gestational-age births was also noted

with weight loss for this category of obesity (Beyerlein 2011).

For women obese class III, no increase in neonatal morbidity or

mortality was observed (Beyerlein 2011).

Blomberg 2011 followed up 46,595 obese women from the

Swedish Medical Birth Registry. The data werestratified according

to obesity classes I, II and III and compared with the latest Insti-

tute of Medicine Guidelines (Rasmussen 2009b). The Blomberg

2011 analysis indicates that all obese women who lose weight in

pregnancy appear to have less risk of caesarean birth and deliver-ing large-for-gestational-age infants, and no significantly increased

risk of developing pre-eclampsia, and other complications associ-

ated with birth and for the infant normally associated with obesity

when compared with weight gains of 5.0 to 9.0 kg. The overall

incidence of large for gestational age infants was 13.2% in obese

women II and III who gained within the current recommenda-

tions for their weight (Rasmussen 2009b), and reduced to 8.8%

if weight was lost (Blomberg 2011).

For heavier women (BMI greater than 40), weight loss in preg-

nancy appears to be more advantageous. In an exploration of the

outcomes of 120,251 pregnant obese women who delivered full-

term live singleton infants where the risks of pre-eclampsia, cae-

sarean birth, small-for-gestation infants and large-for-gestation in-fants were assessed, the results indicated that a weight loss of up to

9 lbs (4kgs) may have minimal risks for women with BMI greater

than 40 (Kiel 2007). The Hinkle 2010 review also indicates that

women with BMI greater than 40 who lose weight during preg-

nancy havebetter outcomes.The lowest absoluteriskof developing

pre-eclampsia, caesarean birth, and infant size being either small-

for-gestational age or large-for-gestational age for these women




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was after a weight loss of zero to 4.1 kg (Hinkle 2010).

Clinical management of pregnancy weight in obese

women

Ideally, women with BMI greater than 30 kg/m² should plan tolose weight before conception according to the National Institute

of Health and Clinical Excellence (NICE) (NICE 2010). In the

UK, NICE 2010 recommends that pregnant women identified as

obese at initial antenatal appointments should be advised about

the potential risks of losing weight whilst pregnant, and provided

with information and support about appropriate diet and exer-

cise. NICE 2010 guidance discourages dieting when pregnant and

obese.

Description of the intervention

There are many interventions that aim to facilitate weight loss in

the non-pregnant population. These interventions areoftenmulti-

component, combining one or more techniques. Health profes-

sionals and/or personnel with a range of training and experience

deliver the interventions.

Interventions used to reduce weight in non-pregnant populations

are defined in this review to provide background information to

the types of interventions that potentially could be used in future

randomised controlled trials designed to reduce weight in obese

pregnantwomen, if sufficientevidenceis providedin observational

studies to support the safety of interventions. Interventions in the

non-pregnant population may include lifestyle interventions that

use techniques such as ’information giving’ related to lifestyle, for

example, nutrition (calorie restriction and eating behaviour mod-

ification) and exercise behaviour modification such as increasing

walking (Blackburn 2010). The delivery of information is vari-

able entailing use of written material, internet, telephone con-

tact and/or mail-based, and group-based or individualised con-

tact (Schroder 2010; Stuart 2005; Witham 2010). Psychological

interventions may also be used. These include techniques that

aim to facilitate behaviour change such as self-help, peer support,

counselling, cognitive behavioural therapy, problem-solving ther-

apy, goal setting, motivational interview techniques, and thera-

pist contact (Pollak 2010; Warziski 2009). Complementary thera-

pies such as acupressure and meditation may also be incorporated

into relevant interventions (Elder 2010; Spadaro 2008). In non-

pregnant populations pharmacological agents such as Metformin,

Sibutramine and Orlistat can be used to reduce weight (Cannon

2009; Warziski 2009), and bariatric procedures such as gastric by-

pass surgery and laparascopic adjustable banding (Richens 2010)

are also utilised in non-pregnant individuals.

Why it is important to do this review

There are currently no evidence-based guidelines for clinical staff

and women related to weight management when obese and preg-

nant. Recent recommendations from NICE in the UK state that

obese women should not diet and deliberately lose weight when

pregnant because of risk of harm to the unborn child (NICE

2010). Furthermore, a Cochrane review has indicated that there isa paucity of evidence to recommend interventions aimed at con-

trolling excessive weight gain in pregnancy (Muktabhant 2012).

However, the risks of obesity, to both the mother and infant, are

substantial when pregnant.

Some obese women lose weight when pregnant (Bianco 1998;

Bish 2009; Cohen 2009; Dietz 2006; Edwards 1996; Oken 2009),

and especially those who are heaviest (Hinkle 2010). There is

insufficient evidence of the known benefits of weight loss when

obese and pregnant, or the harm that may occur to the unborn

baby.

Deliberate attempts to lose weight are common among the non-

pregnant reproductive-aged population (Bish 2005). It is possible

therefore that some women may be dieting to lose weight aroundthe time of conception, and for the weeks prior to pregnancy

being confirmed (Cohen 2009). Furthermore, for some women

pregnancy is an opportunity to evaluate their lifestyle, and many

adjust their diet to eat more healthily for the sake of the child

(Gross 2007). Eating healthier when obese may result in weight

loss. There is a possibility that some obese women maynot disclose

their attempts at weightloss when pregnant because theyare aware

that it is socially unacceptable (Cohen 2009).

As it is clearly apparent that some obese women deliberately try to

lose weight in pregnancy (Bish 2009; Cohen 2009), the maternal

and neonatal outcomes of weight loss in pregnancy when obese

need to be established.

If weight loss in obese pregnant women is beneficial, maternaland infant outcomes may be improved. Postnatal weight retention

will be limited and this may lead to greater control over weight

management in this group in the future. This may improve health

outcomes of future pregnancies. If weightloss is beneficial to obese

pregnantwomen, the development of feasible and acceptable inter-

ventions designed to facilitate weight loss may result in decreased

costs to health services. Furthermore, interventions designed to

reduce weight in obese pregnant women should be investigated to

explore their effectiveness in achieving their aim.

If weight loss is harmful for the obese pregnant woman, the effects

should be identified so that appropriate information and advice

can be developed.

O B J E C T I V E S

To evaluate the effectiveness of interventions that reduce weight

in obese pregnant women.




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M E T H O D S

Criteria for considering studies for this review

Types of studies

We considered all published and unpublished randomised and

quasi-randomised controlled trials, comparing a weight loss inter-

vention with routine care or more than one weight loss interven-

tion. We considered cluster-randomised trials.

Types of participants

Obese pregnant women with a BMI equal to, or greater than 30

(kg/²m).

Types of interventions

All interventions that aim to reduce weight in pregnant women

who are obese such as eating and exercise behaviour modification,

or counselling.

Interventions in any setting.

Studies where the intervention is introduced in pregnancy.

We intended to undertake the following comparisons:

• one intervention versus no intervention;

• one intervention versus another intervention.

Types of outcome measures

Primary outcomes

1. Serious maternal morbidity (admission to high dependency

care) and/or death.

2. Neonatal admission to neonatal intensive care.

3. Perinatal death (including stillbirth).

Secondary outcomes

Maternal outcomes

1. Gestational diabetes.

2. Fetal distress in pregnancy or labour.

3. Postpartum haemorrhage.

4. Caesarean birth.

5. Infection (including wound, urinary tract, perineum, chest

and breast).

6. Weight (loss/gain/no change).

Neonatal outcomes

1. Birthweight less than 2500 g and less than the 10th centile

for gestational age and sex.

2. Birth weight greater than 4000 g or larger than the 90th

centile for gestational age and sex.

3. Preterm birth (birth less than 37 completed weeks of pregnancy).

4. Apgar scores less than seven at five minutes.

5. Hypoglycaemia - as defined by trialists.

Long-term outcomes

1. Maternal weight postpartum.

2. Childhood weight.

Search methods for identification of studies

Electronic searches

We contacted the Trials Search Co-ordinator to search the

Cochrane Pregnancy and Childbirth Group’s Trials Register (31

July 2012).

The Cochrane Pregnancy and Childbirth Group’s Trials Register

is maintained by the Trials Search Co-ordinator and contains trials

identified from:

1. monthly searches of the Cochrane Central Register of

Controlled Trials (CENTRAL);

2. weekly searches of MEDLINE;

3. weekly searches of EMBASE;

4. handsearches of 30 journals and the proceedings of major

conferences;

5. weekly current awareness alerts for a further 44 journals

plus monthly BioMed Central email alerts.

Details of the search strategies for CENTRAL, MEDLINE and

EMBASE, the list of handsearched journals and conference pro-

ceedings, and the list of journals reviewed via the current aware-

ness service can be found in the ‘Specialized Register’ section

within the editorial information about the Cochrane Pregnancy

and Childbirth Group.

Trials identified through the searching activities described above

are each assigned to a review topic (or topics). The Trials Search

Co-ordinator searches the register for each review using the topic

list rather than keywords.

Searching other resources

We did not apply any date restrictions.

We did not apply any language restrictions.

We included abstracts because data and details were limited.

We contacted the authors of studies to obtain further information,

where relevant.



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We used our professional contacts to seek further trial data.

Data collection and analysis

Selection of studies

Threereview authors (Christine Furber, Tina Lavender, and Linda

McGowan) independently assessed for inclusion each study that

was identified through the search strategy. We resolved any dis-

agreement through discussion.

In this version of the review we did not identify any studies for

inclusion. In updates of the review if we do identify trials which

meet our inclusion criteria we will use the methods set out in

Appendix 1 to carry out data extraction, assess bias in included

studies and analyse findings.

R E S U L T S

Description of studies

See: Characteristics of excluded studies.

See Characteristics of excluded studies.The search of the Cochrane Pregnancy and Childbirth Group’s

Trials Register retrieved 63 reports equating to 49 studies. We

applied the eligibility criteria to each study and all were excluded.

In some situations, we emailed the authors of the study to clarify the overall aim of the study. None of the studies identified aimed

to reduce weight in obese pregnant women. See Excluded studies.

Excluded studies

None of the studies retrieved aimed to reduce weight in obese

pregnant women so were not relevant to this review. In total, 38

of the 49 studies retrieved reported results of trials. Eight trials

were excluded as the participants were either not pregnant (two

studies), or not obese (six studies).

Risk of bias in included studies

No studies met the eligibility criteria for inclusion.

Effects of interventions

No studies met the eligibility criteria for inclusion.

D I S C U S S I O N

This review indicates that obesity in pregnancy is of international

concern; most of the studies retrieved from the searches were

from Europe, North America, the Nordics, and Australia and New

Zealand, and a few were conducted in Brazil and Egypt. How-

ever, no randomised controlled trials designed to reduce maternal weight in pregnant obese women were found. The majority of the

excluded randomised controlled trials including obese pregnant

women that were reviewed had outcomes which aimed to man-

age maternal weight gain within the parameters of the Institute

of Medicine Guidance (Medicine 1990), or to reduce excessive

weight gain. Others were designed to improve dietary and exer-

cise behaviours, reduce infant weight, explore pregnancy outcome,

and minimise the effects of diabetes. A range of interventions were

included in these studies including dietary, exercise, and compre-

hensive lifestyle interventions. Others included interventions that

incorporated practices in the delivery of maternity care including

regular maternal weighing in pregnancy, and continuity in the de-

livery of maternity care.Pharmacologicalagents were used in somestudies, butthey were notused to reduceweight. Furthermore,two

studies that used pharmacological interventions did not include

obese women. Metformin is currently being used in two studies to

minimise adverse outcomes for obese pregnant women (Norman

2010; Shehata 2012), however, weight loss is not a planned out-

come.

From retrospective cohort observational studies (Beyerlein 2011;

Blomberg 2011; Oken 2009) for example, it is clear that weight

loss when obese in pregnancy is not unusual, whether this is in-

tentional or not. Weight loss when obese should be monitored

carefully as although emerging observational studies of existing

data indicate that there are some improvements in outcomes suchas incidence of pre-eclampsia, caesarian section and adverse out-

comes at birth for the mother and infant, the increase in small-for-

gestational-age infants is of concern (Beyerlein 2011; Blomberg

2011).

Summary of main results

We found no relevant randomised controlled trials that were eli-

gible for this review.

A U T H O R S ’ C O N C L U S I O N S

Implications for practice

It is interesting to note from observational cohort studies that

obese pregnant women may lose weight and have better outcomes

than those who gain weight within recommended guidance, espe-

cially those who are morbidly obese. However weight loss in mor-

bidly obese pregnant women does not eliminate risks associated




10/29

with pregnancy (Hinkle 2010; Beyerlein 2011; Blomberg 2011).

These observational studies indicate that the impact of weight loss

when obese and pregnant are complex, and also variable across

obese categories. Although there may be lesser likelihood of pre-

eclampsia, caesarean birth and a large for gestational age fetus at

term, the potential for increased risk of small-for-gestational ageinfants indicates that weight loss when pregnant and obese is not

without risk. More robust evidence of the outcomes of weight

loss when pregnant and obese across obesity categories is required

so that we can confidently understand outcomes, especially those

that impact on the neonate.

As there is no evidence from randomised controlled trials of in-

terventions during pregnancy that weight loss in obese pregnant

women is beneficial, recommendations advocating weight reduc-

tion in pregnancy when obese cannot be supported. We suggest

that until evidence is available, no practice recommendations can

be made.

Implications for research

The absence of randomised controlled trials related to reducing

weight in obese pregnant women may be a reflection of the lack of

evidence from observational cohort studies of the safety of weight

loss in this group. There is no robust evidence that indicates the

benefits, or harm, of losing weight when obese and pregnant. Un-

til evidence is available, it may not be appropriate to conduct a

randomised controlled trial designed to promote weight loss in

obese women in pregnancy. Furthermore, it is unlikely that an

ethics committee would provide favourable opinion to any such

study based on current evidence.

More understanding is required of the weight trajectory of obese women during pregnancy. Prospective observational cohort stud-

ies of obese women during pregnancy will provide more data that

explains weight changes for this group, and short and long term

outcomes.Further studies are requiredto explore the efficacy of the

latest guidance from the Institute of Medicine (Blomberg 2011;

Rasmussen 2009b), especially as this guidance has not stratified

recommendations for weight gain across all obese categories ( Artal

2010). Qualitative research will provide more insights into the

weight management strategies utilised by obese women during

pregnancy, especially those who deliberately lose weight.

A C K N O W L E D G E M E N T S

As part of the pre-publication editorial process, this review has

been commented on by four peers (an editor and three referees

who are external to the editorial team) and the Group’s Statistical

Adviser.

R E F E R E N C E S

References to studies excluded from this review

Althuizen 2006 {published data only}

Althuizen A, van Poppel MNM, Seidell JC, van der Wijden

C, van Mechelen W. Design of the New Life(style) study:

a randomised controlled trial to optimise maternal weight

development during pregnancy. BMC Public Health 2006;

6:168.

Angel 2011 {published data only}

Angel MD, De Haene J, Perez M, Hernandez G, Castaneda

D, King JC. Dietary patterns associated with gestational

weight gain and fat mass gain in overweight and obese

pregnant women. FASEB Journal 2011;25:783.15.

Asbee 2009 {published data only}∗ Asbee SM, Jenkins TR, Butler JR, White J, Elliot M,

Rutledge A. Preventing excessive weight gain during

pregnancy through dietary and lifestyle counseling: a

randomized controlled trial. Obstetrics & Gynecology 2009;

113(2 Pt 1):305–12.

Asbee SM, Jenkins TR, Butler JR, White J, Elliott M,

Rutledge A. Dietary counselling prevents excessive weight

gain during pregnancy A randomized controlled trial.

Obstetrics & Gynecology 2008;111(4 Suppl):6S.

Badrawi 1993 {published data only}∗ Badrawi H, Hassanein MK, Badraoui MHH, Wafa YA,

Shawky HA, Badrawi N. Pregnancy outcome in obesepregnant mothers. New Egyptian Journal of Medicine 1993;

8(6):1717–26.

Badrawi H, Hassanein MK, Badraoui MHH, Wafa YA,

Shawky HA, Badrawi N. Pregnancy outcome in obese

pregnant women. Journal of Perinatal Medicine 1992;20

(Suppl. 1):203.

Boileau 1968 {published data only}

Boileau PA. Control of weight -gain during pregnancy:

Use of diethylpropion hydrochloride. Applied Therapeutics

1968;10:763–5.

Brand-Miller 2011 {published data only}

Brand-Miller J. A randomized, two-arm parallel dietary

intervention study to compare the effects of consuming a low glycemic diet or wholegrain high fibre diet on infant

birth weight and body composition, complications related

to Gestational Diabetes Mellitus (GDM) and progression to

GDM diagnosis in women at high-risk of GDM. Australian

New Zealand Clinical Trials Register (www.anzctr.org.au)

2011; Vol. (accessed 11 February 2011).

Brownfoot 2011 {published data only}

Brownfoot F. In antenatal women, does weighing at each




11/29

visit compared with routine antenatal care reduce the

incidence of excessive weight gain during pregnancy?.

http://www.anzctr.org.au/ACTRN12610000331033.aspx

(accessed 27 July 2011).

Callaway 2010 {published data only}

Byrne NM, Groves AM, McIntyre HD, Callaway LK.

Changes in resting and walking energy expenditure and

walking speed during pregnancy in obese women. American

Journal of Clinical Nutrition 2011;94(3):819–30.

Callaway L. A randomized controlled trial using exercise to

reduce gestational diabetes and other adverse maternal and

neonatal outcomes in obese pregnant women - the pilot

study. Australian Clinical Trials Registry (www.actr.org.au)

(accessed 21 June 2007).

Callaway L, McIntyre D, Colditz P, Byrne N, Foxcroft

K, O’Connor B. Exercise in obese pregnant women: a

randomized study to assess feasibility. Hypertension in

Pregnancy 2008;27(4):549.∗ Callaway LK, Colditz PB, Byrne NM, Lingwood BE,

Rowlands IJ, Foxcroft K, et al.Prevention of gestational

diabetes. Feasibility issues for an exercise intervention in

obese pregnant women. Diabetes Care 2010;33(7):1457–9.

Foxcroft KF, Rowlands IJ, Byrne NM, McIntyre HD,

Callaway LK, BAMBINO group. Exercise in obese pregnant

women: the role of social factors, lifestyle and pregnancy

symptoms. BMC Pregnancy and Childbirth 2011;11:4.

Chasen-Taber 2011 {published data only}∗ Chasen-Taber L, Marcus BH, Stanek E, Ciccolo JT,

Marquez DX, Solomon MD, et al.A randomized controlled

trial of prenatal physical activity to prevent gestational

diabetes: design and methods. Journal of Women’s Health

2009;18(6):851–9.

Chasen-Taber L, Silveira M, Marcus BH, Braun B, Stanek

E. Markenson G. Feasibility and efficacy of a physicalintervention among pregnant women: The behaviors

affecting Baby and You (B.A.B.Y.) study. Journal of Physical

Activity and Health 2011;8(Suppl 2):S228–S238.

Dodd 2011 {published data only}

Dodd J. Limiting weight gain in overweight and obese

women during pregnancy to improve health outcomes:

a randomised trial. Australian Clinical Trials Registry

(www.actr.org.au) (accessed 21 June 2007).∗ Dodd J, Turnbull DA, McPhee AJ, Wittert G, Crowther

CA, Robinson JS. Limiting weight gain in overweight

and obese women during pregnancy to improve health

outcomes: the LIMIT randomised controlled trial. BMC

Pregnancy and Childbirth 2011;11:79.

Faucher 2008 {published data only}Faucher MA. Promotoras de salud and portion control:

a community intervention aimed at weight loss in low-

income Mexican-American women. Journal of Midwifery

and Women’s Health 2008;53(5):482.

Guelinckx 2010 {published data only}

Guelinckx I, Devlieger R, Mullie P, Vansant G. Effect of

lifestyle intervention on dietary habits, physical activity,

and gestational weight gain in obese pregnant women: a

randomized controlled trial. American Journal of Clinical

Nutrition 2010;91(2):373–80.

Haakstad 2011 {published data only}

Haakstad LAH, Bo K. Effect of regular exercise on

prevention of excessive weight gain in pregnancy:

a randomised controlled trial. European Journal of

Contraception and Reproductive Health Care 2011;16(2):

116–25.

Harrison 2011 {published data only}

Harrison CL, Lombard CB, Gibson-Helm M, Deeks

A, Teede HJ. Limiting excess weight gain in high-risk

pregnancies: A randomized controlled trial. Endocrine

Reviews 2011;32(3 Meeting Abstracts):P1–466.

Huang 2011 {published data only}

Huang TT, Yeh CY, Tsai YC. A diet and physical activity

intervention for preventing weight retention among

Taiwanese childbearing women: a randomised controlled

trial. Midwifery 2011;27(2):257–64.

Hui 2012 {published data only}

Hui A, Back L, Ludwig S, Gardiner P, Sevenhuysen G, Dean

H, et al.Lifestyle intervention on diet and exercise reduced

excessive gestational weight gain in pregnant women under

a randomised controlled trial. BJOG: an international

journal of obstetrics and gynaecology 2012;119(1):70–7.

Jackson 2011 {published data only}

Jackson RA, Stotland NE, Caughey AB, Gerbert B.

Improving diet and exercise in pregnancy with Video

Doctor counseling: a randomized trial. Patient Education

and Counseling 2011;83(2):203–9.

Jeffries 2009 {published data only}

Jeffries K, Shub A, Walker SP, Hiscock R, Permezel M.

Reducing excessive weight gain in pregnancy: a randomised

controlled trial. Medical Journal of Australia 2009;191(8):429–33.

Koushkie 2003 {published data only}

Koushkie M, Nikbakht H, Parsanezhad ME, Jahromi

BN, Salami F, Khoshnam E. Aerobic exercise during third

trimester of pregnancy, and pregnancy symptoms and

outcomes. Canadian Journal of Applied Physiology 2003;28

Suppl:S73.

Krummel 2009 {published data only}

Krummel DA. DHA supplements to improve insulin

sensitivity in obese pregnant women (the omega-3

pregnancy study). http://clinicaltrials.gov/ct2/show/

NCT00865683 (accessed 31 July 2009).

Lavender 2011 {published data only}Lavender T. A pilot randomised controlled trial to evaluate

the impact of attending The Lifestyle Course (TLC) on the

health of pregnant women with a Body MassIndex (BMI) of

30kg/m2 or more and their babies. http://www.controlled-

trials.com/isrctn/pf/09432573 (accessed 4 July 2011).

Lombard 2011 {published data only}

Lombard C, Harrison C, Teede H. A randomized controlled

trial investigating self-weighing and the prevention of excess




12/29

weight gain in early pregnancy. Endocrine Reviews 2011;32

(3 Meeting Abstracts):P2–768.

Louie 2011 {published data only}

Louie JCY, Markovic TP, Perera N, Foote D, Petocz P, Ross

GP, et al.A randomized controlled trial investigating the

effects of a low-glycemic index diet on pregnancy outcomes

in gestational diabetes mellitus. Diabetes Care 2011;34(11):

2341–6.

Luoto 2011 {published data only}

Luoto R, Kinnunen TI, Aittasalo M, Kolu P, Raitanen J,

Ojala K, et al.Primary prevention of gestational diabetes

mellitus and large-for-gestational-age newborns by lifestyle

counseling: a cluster-randomized controlled trial. PLoS

Medicine 2011;8(5):1–11.

Magee 1990 {published data only}

Magee MS, Knopp RH, Benedetti TJ. Metabolic effects of

1200-kcal diet in obese pregnant women with gestational

diabetes. Diabetes 1990;39:234–40.

Moholdt 2011 {published data only}

Moholdt TT, Salvesen K, Ingul CB, Vik T, Oken E,Morkved S. Exercise Training in Pregnancy for obese

women (ETIP): study protocol for a randomised controlled

trial. Trials 2011;12:154.

Moses 2006 {published data only}

Moses RG, Luebcke M, Davis WS, Coleman KJ, Tapsell

LC, Petocz P, et al.Effect of a low-glycemic-index diet

during pregnancy on obstetric outcomes. American Journal

of Clinical Nutrition 2006;84:807–12.

Moses 2009 {published data only}

Moses RG, Barker M, Winter M, Petocz P, Brand-Miller J.

Can a low - glycemic index diet reduce the need for insulin

in gestational diabetes mellitus? A randomized controlled

trial. Diabetes Care 2009;32(6):996–1000.Nagle 2011 {published data only}

Nagle C, Skouteris H, Hotchin A, Bruce L, Patterson D,

Teale G. Continuity of midwifery care and gestational

weight gain in obese women: a randomised controlled trial.

BMC Public Health 2011;11:174.

Nascimento 2011 {published data only}

Nascimento SL, Surita FG, Parpinelli MA, Siani S, Pinto

e Silva JL. The effect of an antenatal physical exercise

programme on maternal/perinatal outcomes and quality of

life in overweight and obese pregnant women: a randomised

clinical trial. BJOG: an international journal of obstetrics and

gynaecology 2011;118(12):1455–63.

Norman 2010 {published data only}∗ Norman J. A multicentre randomised placebo controlled

clinical trial of metformin versus placebo in pregnant

women to reduce the risk of obesity and metabolic

syndrome in their babies. http://www.controlled-trials.com/

ISRCTN51279843/EMPOWaR (accessed 2012).

Weeks A. Does metformin reduce excess bir thweight

in offspring of obese pregnant women? A randomised

controlled trial of efficacy, exploration of mechanisms

and evaluation of other pregnancy complications. http://

www.eme.ac.uk/projectfiles/0824609protocol.pdf (accessed

12.10.2011).

Ong 2009 {published data only}

Ong MJ, Guelfi KJ, Hunter T, Wallman KE, Fournier

PA, Newnham JP. Supervised home-based exercise may

attenuate the decline of glucose tolerance in obese pregnant women. Diabetes & Metabolism 2009;35(5):418–21.

Parat 2009 {published data only}

Parat S. Impact of education during pregnancy in overweight

pregnant women (ETOIG). http://clinicaltrials.gov/ct2/

show/NCT00804765 (accessed 4 January 2009).

Phelan 2011 {published data only}

Phelan S, Phipps MG, Abrams B, Darroch F, Schaffner A,

Wing RR. Factors associated with success in the “fit for

delivery” intervention to reduce excessive gestational weight

gain. Obesity 2011;19(Suppl 1):S95.∗ Phelan S, Phipps MG, Abrams B, Darroch F, Schaffner

A, Wing RR. Randomized trial of a behavioral intervention

to prevent excessive gestational weight gain: the Fit for

Delivery Study. American Journal of Clinical Nutrition

2011;93(4):772–9.

Polley 2002 {published data only}

Polley BA, Wing RR, Sims CJ. Randomized controlled

trial to prevent excessive weight gain in pregnant women.

International Journal of Obesity & Related Metabolic

Disorders: Journal of the International Association for the

Study of Obesity 2002;26(11):1494–502.

Poston 2009 {published data only}∗ Poston L. Improving pregnancy outcome in obese women:

a feasibility study. http://www.controlled-trials.com/

ISRCTN89971375 (accessed 22 June 2012).Poston L, Holmes B, Kinnunen T, Croker H, Bell R,

Sanders T, et al.A complex intervention to improve outcome

in obese pregnancies; the upbeat study. Archives of Disease

in Childhood: Fetal and Neonatal Edition 2011;96(Suppl 1):

Fa97.

Quinlivan 2011 {published data only}

Quinlivan J. A randomised trial of a multidisciplinary

teamcare approach involving obstetric, dietary and clinical

psychological input in obese pregnant women to reduce the

incidence of gestational diabetes. Australian Clinical Trials

Register (www.actr.org.au) (accessed 6 December 2005).∗ Quinlivan JA, Lam LT, Fisher J. A randomised trial of a

four-step multidisciplinary approach to the antenatal careof obese pregnant women. Australian and New Zealand

Journal of Obstetrics and Gynaecology 2011;51(2):141–6.

Rae 2000 {published data only}

Rae A, Bond D, Evans S, North F, Roberman B, Walters B.

A randomised controlled trial of dietary energy restriction

in the management of obese women with gestational

diabetes. Australian & New Zealand Journal of Obstetrics &

Gynaecology 2000;40(4):416–22.




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Rhodes 2010 {published data only}

Pawlak DB. Glycemic load and infant birth weight in

pregnant overweight/obese women. http://clinicaltrials.gov/

ct2/show/NCT00364403 (accessed 21 June 2007) 2007.∗ Rhodes ET, Pawlak DB, Takoudes TC, Ebbeling CB,

Feldman HA, Lovesky MM, et al.Effects of a low-glycemic

load diet in overweight and obese pregnant women: a pilotrandomized controlled trial. American Journal of Clinical

Nutrition 2010;92(6):1306–15.

Santos 2005 {published data only}

Santos IA, Stein R, Fuchs SC, Duncan BB, Ribeiro JP,

Kroeff LR, et al.Aerobic exercise and submaximal functional

capacity in overweight pregnant women: a randomized

trial. Obstetrics & Gynecology 2005;106(2):243–9.

Shehata 2012 {published data only}∗ Shehata H. Metformin in obese non-diabetic pregnant

women (MOP). http://clinicaltrilas.gov/ct2/show/

NCT01273584 [Accessed 17th September 2012] 2012.

Silverman 1971 {published data only}

Silverman M, Okun R. The use of an appetite suppressant(diethylpropion hydrochloride) during pregnancy. Current

Therapeutic Research, Clinical and Experimental 1971;13:

648–53.

Szmeja 2011 {published data only}

Szmeja MA, Grivell RM, Deussen AR, Dodd JM.

Evaluation of information provision to women who are

overweight or obese during pregnancy. Journal of Paediatrics

and Child Health 2011;47(Suppl 1):78.

Teede 2011 {published data only}

Teede HJ, Harrison CL, Gibson-Helm M, Lombard CB.

Improving physical activity in high-risk pregnancies: a

randomized controlled trial. Endocrine Reviews 2011;32(3

Meeting Abstracts):P1–467.

Te Morenga 2010 {published data only}Te Morenga L, Williams S, Brown R, Mann J. Effect of a

relatively high-protein, high fiber diet on body composition

and metabolic risk factors in overweight women. European

Journal of Clinical Nutrition 2010;64:1323–1.

Thornton 2009 {published data only}

Thornton YS, Smarkola C, Kopacz SM, Ishoof SB. Perinatal

outcomes in nutritionally monitored obese pregnant

women: a randomized clinical trial. Journal of the National

Medical Association 2009;101:569–77.

Vinter 2011 {published data only}

Vinter C. Lifestyle and pregnancy: the clinical effect of

lifestyle intervention during pregnancy in obese women

(LiP). ClinicalTrials.gov (http:clinicaltrials.gov) (accessed

September 2011).

Vinter C, Jensen D, Ovesen P, Beck-Nielsen H, Lamont R,

Jorgensen J. Postpartum weight retention and breastfeeding

among obese women from the LiP (Lifestyle in Pregnancy)

Study. Acta Obstetricia et Gynecologica Scandinavica 2012;

91(Suppl 159):141–2.∗ Vinter CA, Jensen DM, Ovesen P, Beck-Nielsen H,

Jorgensen JS. The LiP (Lifestyle in Pregnancy) study: a

randomized controlled trial of lifestyle intervention in

360 obese pregnant women. Diabetes Care 2011;34(12):

2502–7.

Vitolo 2011 {published data only}

Vitolo MR, Fraga Bueno MS, Mendes Gama C. Impact of

a dietary counseling program on the gain weight speed of

pregnant women attended in a primary care service. Revista

Brasileira de Ginecologia e Obstetricia 2011;33(1):13–9.

Wolff 2008 {published data only}

Wolff S, Legarth J, Vangsgaard K, Toubro S, Astrup A.

A randomized controlled trial of the effects of dietary

counseling on gestational weight gain and glucose

metabolism in obese pregnant women. International Journal

of Obesity 2008;32:495–501.

Additional references

Abrams 1995

Abrams B, Selvi, S. Maternal weight gain pattern and birth

weight. Obstetrics & Gynecology 1995;86:163–9.

Artal 2010 Artal R, Lockwood CJ, Brown HL. Weight gain

recommendations in pregnancy and the obesity epidemic.

Obstetrics & Gynecology 2010;115:152–5.

Baeton 2001

Baeten JM, Bukusi EA, Lambe M. Pregnancy complications

and outcomes among overweight and obese nulliparous

women. American Journal of Public Health 2001;91(3):

436–40.

Beyerlein 2011

Beyerlein A, Schiessl B, Lack N, von Kries R. Associations

of gestational weight loss with birth-related outcome: a

retrospective cohort study. BJOG: an international journal

of obstetrics and gynaecology 2011;118:55–61.

Bianco 1998

Bianco AT, Smilen SW, Davis Y, Lopez S, Lapinski R,

Lockwood CJ. Pregnancy outcome and weight gain

recommendations for the morbidly obese woman. Obstetrics

& Gynecology 1998;91:97–102.

Bish 2005

Bish CL, Blanck HM, Serdula MK, Marcus M, Kohl HW

3rd, Khan LK. Diet and physical activity behaviors among

Americans trying to lose weight: 2000 Behavioral Risk

Factor Surveillance System. Obesity Research 2005;13(3):

596–607.

Bish 2009

Bish CL, Chu SY, Shapiro-Mendoza CK, Sharma AJ,

Blanck HM. Trying to lose or maintain weight during pregnancy - United States, 2003. Maternal Child Health

Journal 2009;13:286–92.

Blackburn 2010

Blackburn GL, Wollner S, Heynsfield SB. Lifestyle

interventions for the treatment of class III obesity: a primary

target for nutrition medicine in the obesity epidemic.

American Journal of Clinica l Nutrition 2010;91 Suppl:

289S–292S.




14/29

Blomberg 2011

Blomberg M. Maternal and neonatal outcomes among

obese women with weight gain below the new Institute of

Medicine recommendations. Obstetrics & Gynecology 2011;

117(5):1065–0.

Bodnar 2010

Bodnar LM, Siega-Riz AM, Simhan N, Himes KP, Abrams

B. Severe obesity, gestational weight gain, and adverse birth

outcomes. American Journal of Clinical Nutrition 2010;91:

1642–8.

Cannon 2009

Cannon CP, Kumar A. Treatment of overweight and obesity:

lifestyle, pharmacologic, and surgical options. Clinical

Cornerstone 2009;9(4):55–71.

Carmichael 1997

Carmichael S, Abrams B, Selvin S. The pattern of maternal

weight gain in women with good pregnancy outcomes.

American Journal of Public Health 1997;87(12):1984–8.

Carmichael 2003

Carmichael SL, Shaw GM, Schaffer DM, Laurent C,Selvin S. Dieting behaviors and risk of neural tube defects.

American Journal of Epidemiology 2003;158:1127–31.

Chu 2007

Chu SY, Kim SY, Lau J, Schmid HY, Dietz PM, Callaghan

WM, et al.Maternal obesity and risk of stillbirth: a meta

analysis. American Journal of Obstetrics & Gynecology 2007;

197(3):223–8.

Chu 2009

Chu SY, Callaghan WM, Bish CL, D’Angelo D. Gestational

weight gain by body mass index among US women

delivering live births, 2004-2005: fuelling future obesity.

American Journal of Obstetrics and Gynecology 2009;200(3):

271.e1–7.

Cohen 2009

Cohen JH, Kim H. Sociodemographic and health

characteristics associated with attempting weight loss during

pregnancy. Preventing Chronic Disease 2009;6(1):A07.

Dawes 1991

Dawes MG, Grudzinskas JG. Patterns of maternal weight

gain in pregnancy. British Journal of Obstetrics and

Gynaecology 1991;98:195–201.

Dewey 1994

Dewey KG, McCrory MA. Effects of dieting and physical

activity on pregnancy and lactation. American Journal of

Clinical Nutrition 1994;59 Suppl:446S–535S.

Dietz 2006

Dietz PM, Callaghan WM, Cogswell ME, Morrow B, FerreC, Schieve LA. Combined effects of prepregnancy body

mass index and weight gain during pregnancy on the risk of

preterm delivery. Epidemiology 2006;17(2):170–7.

Doherty 2006

Doherty DA, Magann EF, Franxis J, Morrison JC,

Newnham JP. Pre-pregnancy body mass index and

pregnancy outcomes. International Journal of Gynecology &

Obstetrics 2006;95:242–7.

Doherty 2008

Doherty L, Norwitz ER. Prolonged pregnancy: when

should we intervene?. Current Opinion in Obstetrics and

Gynecology 2008;20(6):519–27.

Edwards 1996

Edwards LE, Hellerstedt WL, Alton IR, Story M, Himes

JH. Pregnancy complications and birth outcomes in obese

and normal-weight women: effects of gestational weight

change. Obstetrics & Gynecology 1996;87:389–94.

Egger 1997

Egger M, Davey Smith G, Schneider M, Minder C. Bias

in meta-analysis detected by a simple, graphical test. BMJ

1997;315(7109):629–34.

Elder 2010

Elder C, Gallison C, Lindberg NM, DeBar L, Funk K,

Ritenbaugh C, et al.Randomized trial of Tapas Acupressure

Technique for weight loss maintenance: rationale and study

design. Journal of Alternative & Complementary Medicine

2010;16(6):683–90.

Feig 1998

Feig DS, Naylor CD. Eating for two: are guidelines for

weight gain during pregnancy too liberal?. Lancet 1998;

351:1054–5.

Fejzo 2009

Fejzo MS, Poursharif B, Korst LM, Munch S, MacGibbon

KW, Romero R, et al.Symptoms and pregnancy outcomes

associated with extreme weight loss among women with

hyperemesis gravidarum. Journal of Women’s Health 2009;

18(12):1981–7.

Flenady 2011

Flenady V, Koopmans L, Middleton P, Froen JF, Smith GC,

Gibbons K, et al.Major risk factors for stillbirth in high-

income countries: a systematic review and meta-analysis.Lancet 2011;377:1331–40.

Gross 2007

Gross H, Pattison H. Sanctioning Pregnancy. A Psychological

Perspective on the Paradoxes and Culture of Research. London

and New York: Routledge, 2007.

Harbord 2006

Harbord RM, Egger M, Sterne JA. A modified test for

small-study effects in meta-analyses of controlled trials

with binary endpoints. Statistics in Medicine 2006;25(20):

3443–57.

Herrmann 2001

Herrmann TS, Siega-Riz AM, Hobel CJ, Aurora C, Dunkel-

Schetter C. Prolonged periods without food intake during pregnancy increase risk for elevated maternal corticotropin-

releasing hormone concentrations. American Journal of

Obstetrics and Gynecology 2001;185(2):403–12.

Heslehurst 2008

Heslehurst N, Simpson L, Ells J, Rankin J, Wilkinson J,

Lang R, et al.The impact of maternal BMI on pregnancy

outcomes with immediate short-term obstetric resource

implications: a meta-analysis. Obesity 2008;9:635–83.




15/29

Higgins 2011

Higgins JPT, Green S, editors. Cochrane Handbook for

Systematic Reviews of Interventions Version 5.1.0 [updated

March 2011]. The Cochrane Collaboration, 2011.

Available from www.cochrane-handbook.org.

Hinkle 2010Hinkle SN, Sharma AJ, Dietz PM. Gestational weight

gain in obese mothers and associations with fetal growth.

American Journal of Clinical Nutrition 2010;92:644–51.

Johnson 1995

Johnson JW, Yancey MK. A critique of the new

recommendations for weight gain in pregnancy. American

Journal of Obstetrics and Gynecology 1995;174:254–8.

Kerrigan 2009

Kerrigan AM, Kingdon C. Maternal obesity and pregnancy:

a retrospective study. Midwifery 2010;26(1):138–46.

Kiel 2007

Kiel DW, Dodson EA, Artal R, Boehner TK, Leet TL.

Gestational weight gain and pregnancy outcomes in obese women. Obstetrics & Gynecology 2007;110(4):752–8.

Knight 2010

Knight M, Kurinczuk JJ, Spark P, Brocklehurst P, on

behalf of the UK Obstetric Surveillance System. Extreme

obesity in pregnancy in the United Kingdom. Obstetrics &

Gynecology 2010;115(5):989-97.

Krakowiak 2012

Krakowiak P, Walker CK, Bremer AA, Baker AS, Ozooff

S, Hansen RL, et al.Maternal metabolic conditions and

risk for autism and other neurodevelopmental disorders.

Pediatrics 2012;129(5):e1121–8.

Kramer 2003Kramer MS, Kakuma R. Energy and protein intake in

pregnancy. Cochrane Database of Systematic Reviews 2003,

Issue Issue 4. [DOI: 10.1002/14651858.CD000032]

Linne 2003

Linne Y, Dye L, Barkelin B, Rossner S. Weight development

over time in parous women: The SPAWN study: 15

years follow-up. International Journal of Obesity 2003;27:

1516–22.

Medicine 1990

Institute of Medicine. Nutrition During Pregnancy .

Washington DC: National Academy Press, 1990.

Metwally 2008

Metwally M, Ong KJ, Ledger WL, Chiu T. Does high body mass index increase the risk of miscarriage after spontaneous

and assisted conception? A meta-analysis of th evidence.

Fertility and Sterility 2008;90(3):714–26.

Muktabhant 2012

Muktabhant B, Lumbiganon P, Ngamjarus C, Dowswell T.

Interventions for preventing excessive weight gain during

pregnancy. Cochrane Database of Systematic Reviews 2012,

Issue 4. [DOI: 10.1002/14651858.CD007145.pub2]

NICE 2010

National Institute for Health and Clinical Excellence.

Weight Management Before, During and After Pregnancy .

London: NICE, 2010.

Oken 2009

Oken E, Kelinman KP, Belfort MB, Hammitt JK, Gillman

MW. Associations of gestational weight gain with short and

longer-term maternal and child health outcomes. American

Journal of Epidemiology 2009;170(2):173–80.

Oleson 2006

Oleson AW, Westergaard JG, Olsen J. Prenatal risk

indicators of a prolonged pregnancy: the Danish Birth

Cohort 1998-2001. Acta Obstetricia et Gynecologica

Scandinavica 2006;85(11):1338–41.

Olson 2009

Olson CM, Strawderman MS, Dennison BA. Maternal

weight gain during pregnancy and child weight at age 3

years. Maternal and Child Health Journal 2009;13:839–46.

Ovesen 2011

Oveson P, Tasmussen S, Kesmodel U. Effect of prepregnancy maternal overweight and obesity on pregnancy outcome.

Obstetrics & Gynecology 2011;118:305–12.

Pollak 2010

Pollack KI, Alexander SC, Coffman CJ, Tulsky JA, Lyna P,

Dolor RJ, et al.Physician communication techniques and

weight loss in adults Project CHAT. American Journal of

Preventive Medicine 2010;39(4):321–8.

Rankin 2010

Rankin J, Tennant PWG, Stothard KJ, Bythell M,

Summerbell CD, Bell R. Maternal body mass index and

congenital anomaly risk: a cohort study. International

Journal of Obesity 2010;34:1371–80.

Rasmussen 2009a Rasmussen KM Catalano PM, Yaktine AL. New guidelines

for weight gain during pregnancy: what obstetricians/

gynaecologists should know. Current Opinion in Obstetrics

and Gynecology 2009;21:521–6.

Rasmussen 2009b

Rasmussen KM, Yaktine AL, eds. Weight Gain During

Pregnancy: Reexamining the Guidelines . Washington DC:

The National Academies Press, 2009.

RevMan 2011

The Nordic Cochrane Centre, The Cochrane Collaboration.

Review Manager (RevMan). 5.1. Copenhagen: The Nordic

Cochrane Centre, The Cochrane Collaboration, 2011.

Richens 2010

Richens Y, Fiennes A. Bariatric surgery and care of pregnant

women. In: Richens Y, Lavender T editor(s). Care for

Pregnant Women Who Are Obese . London: Quay Books,

2010:19–27.

Rode 2007

Rode L, Heggard HK, Kjaergaard H, Moller LF, Tabor

A, Ottesen B. Association between maternal weight gain

and birth weight. Obstetrics & Gynecology 2007;109(6):

1309–15.




16/29

Rooney 2005

Rooney BL, Schauberger CW, Mathiason MA. Impact of

perinatal weight change on long-term obesity and obesity-

related illnesses. Obstetrics & Gynecology 2005;106(6):

1349–56.

Schroder 2010Schroder KEE. Computer-assisted dieting: effects of a

randomised controlled intervention. Psychology and Health

2010;25:519–34.

Sebire 2001

Sebire N, Jolly M, Harris J, Wadsworth J, Joffe M, Beard

R, et al.Maternal obesity and pregnancy outcome: a study

of 287,213 pregnancies In London. International Journal

of Obesity and Related Metabolic Disorders 2001;25(8):

1175–82.

Spadaro 2008

Spadaro KC. Weight Loss: Exploring Self-regulation Through

Mindfulness Meditation [PhD dissertation] . Pittsburgh:University of Pittsburgh, 2008.

Stein 1995

Stein AD, Ravelli ACJ, Lumey LH. Famine, third-trimester

pregnancy weight gain, and intrauterine growth: the Dutch

famine birth cohort study. Human Biology 1995;67(1):

135–49.

Stein 2004

Stein AD, Zybert PA, Van der Bor M, Lumer LH.

Intrauterine famine exposure and body proportions at

birth: the Dutch hunger winter. International Journal of

Epidemiology 2004;33:831–6.

Stothard 2009

Stothard KJ, Tennat PWG, Bell R, Rankin, J. Maternal

overweight and obesity and the risk of congenital anomalies.

JAMA 2009;3016:636–50.

Stuart 2005

Stuart WP, Broome ME, Smith BA, Weaver M. An

integrative review of interventions for adolescent weight

loss. Journal of School Nursing 2005;21(2):77–85.

Warziski 2009

Warziki M, Yang K, Hravnak M, Sereika SM, Ewing

LJ, Burke LE. Randomized clinical trials of weight loss

maintenance. Journal of Cardiovascular Nursing 2009;24(1):

58–80.

Witham 2010

Witham MD, Avenell A. Interventions to achieve long-term

weight loss in obese older people. A systematic review and

meta-analysis. Age and Ageing 2010;39:176–84.

World Health Organization 2000

World Health Organization. . Obesity: Preventing and

Managing the Global Epidemic . Geneva: WHO, 2000.

World Health Organization 2006

World Health Organization. Overweight and Obesity. Fact

sheet N°311. Geneva: WHO, 2006.

Zaninotto 2006

Zaninotto P, Wardle H, Samakakis E, Mindell J, Head

J. Forecasting Obesity to 2010 . London: Department of

Health, 2006.

Zhang 2007

Zhang J, Bricker L, Wray S, Quenby S. Poor uterine

contractility in obese women. BJOG: an international

journal of obstetrics and gynaecology 2007;114:343–8.∗ Indicates the major publication for the study




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C H A R A C T E R I S T I C S O F S T U D I E S

Characteristics of excluded studies [ordered by study ID]

Study Reason for exclusion

Althuizen 2006 This paper is a protocol of a study in The Netherlands. The intervention (the New Life(style) intervention

program) is not aimed at reducing weight in obese women, but at helping pregnant women to gain weight

within IOM guidelines. The authors were emailed (March 2012) and they confirmed that the study is now

complete. The author confirmed that the study was not aimed at obese women although there were no weight

restrictions on recruitment. Of the 250 women in the sample, only 8 were obese

Angel 2011 This is a brief conference abstract of a randomised controlled trial in the US. The intervention did not aim to

reduce weight in obese pregnant women so has been excluded

Asbee 2009 Brief conference abstract of a randomised controlled trial in the US. This Intervention did not aim to reduce weight in obese pregnant women but prevent excessive weight gain. It is also not clear whether the participants

were obese or not

Badrawi 1993 ThisIntervention did not aim toreduce weight inobese pregnant women but toinvestigate pregnancy outcome

when obese pregnant women were given either a 1500-2000 Kcal daily diet compared to a diet of no restriction.

The abstract reports that those on an unrestricted diet had a high rate of weight gain but there is no information

about the intervention group weight. The study is excluded as the intervention did not aim to reduce maternal

weight

Boileau 1968 This report of a randomised controlled trial in Canada included an intervention that did not aim to reduce

weight in obese pregnant women, but to evaluate the anorexic efficacy of Diethylproprion hydrochloride in

continuous release formulation. Some participants lost weight in the data. It is not clear if these women were

obese when they commenced the study as BMI was not reported. Maternal weight on entry to the study wasassessed using the author’s ’office standard’ of more than 2-3 pounds per month

Brand-Miller 2011 The intervention will not aim to reduce weight so is not applicable to this review. The intervention is a low

glycaemicdiet compared with a whole grain diet. The aim of the study is to compare the effects of the two diets.

Accessed from the Australian New Zealand Clinical Trials Registry (ANZCTR) (ACTRN1261000001055).

Brownfoot 2011 The intervention is maternal weight measurement recordings during routine antenatal care compared with

antenatal care that does not include weighing. The aim is to evaluate whether weighing at each antenatal visit

reduces excessive weightgainin pregnancy. Itis notclear ifobesepregnant women will be directly targeted forthe

study. As the intervention does not aim to reduce maternal weight in obese women in pregnancy, it is excluded.

Accessed from the Australian New Zealand Clinical Trials Registry (ANZCTR) (ACTRN12610000331033).

Callaway 2010 The intervention was a highly supported individualised exercise intervention versus usual activity. The inter-

vention was not designed to reduce weight in obese pregnant women so is not relevant for this review. Although

theparticipants were reported as being obese, changes to weightor BMI are notreported in the study. The study

was a pilot to explore the feasibility of an individualised exercise programme to prevent gestational diabetes in

obese pregnant women



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(Continued)

Chasen-Taber 2011 The intervention was a highly supported individualised exercise intervention versus provision of a booklet

about health and wellness in pregnancy. The intervention was not designed to reduce weight in obese pregnant

women so is not relevant for this review. Although the participants were reported as being obese, changes to weight or BMI are not reported in the study. The study was a pilot to explore the feasibility of an individualised

exercise programme to prevent gestational diabetes in obese pregnant women. This study was completed in

the US

Dodd 2011 The intervention consists of comprehensive diet and lifestyle advice based on behavioural techniques delivered

by a dietician and trained researchers.Dietary advice will be based on current Australian guidelines. The control

group receive usual antenatal care. A power calculation indicates that 2180 women are required for the study.

The authors were emailed March 2012 who confirmed that the study is now complete and results will be

published in approximately 1 year. The study is excluded as the intervention does not aim to reduce weight in

obese pregnant women

Faucher 2008 This is a conference abstract. The abstract describes a pilot intervention in portion control that is aimed to

lead to weight loss in low-income women. It is not clear if the women were obese. It is clear that pregnant women were not included in the study. The abstract is excluded as the participants were not pregnant

Guelinckx 2010 This is a randomised controlled trial including 195 obese pregnant women conducted in Belgium. Women

were randomised to 1 of 3 groups: nutritional advice from a brochure versus brochure and lifestyle advice from

a nutritionist versus usual care. Outcomes were dietary habits, physical activity, weight gain in pregnancy and

obstetric and neonatal outcomes. It is reported in the paper that gestational weight gain was not significantly

different between the groups, and did not decrease in the 2 intervention groups. The study is excluded as the

intervention did not aim to reduce weight in obese pregnant women

Haakstad 2011 This is a randomised controlled trial - assessor blinded carried out in Norway. The participants were sedentary,

nulliparous pregnant women - obese women were not directly targeted but 11 of the 105 participants were

obese. The intervention was an exercise group versus usual care. The outcomes were maternal weight gain and

proportion of women gaining above the IOM guidelines.The results indicate that there was no difference in

maternal weight gain between both groups. The study is excluded as the intervention did not aim to reduce

weight in obese pregnant women, but to prevent excessive weight gain

Harrison 2011 This was a brief conference abstract of a randomised controlled trial in Australia. The intervention was a low

intensity lifestyle designed to reduce excessive weight gain, not reduce weight, in overweight pregnant women.

The outcome was to assess the efficacy of the intervention, therefore the study has been excluded

Huang 2011 This isa randomised controlled trial in Taiwan. The participants were all pregnant women (n = 240), including

some who were obese.The intervention included individual counselling about diet and physical exercise over

2 time periods. 1 group through pregnancy till 6 months postpartum, and the other from birth till 6 months

postpartum. The aim of the study was to explore the effect of the interventions on weight retention. The results

indicate that the intervention is effective for reducing postpartum weight retention. However, the study didnot aim to reduce weight in obese pregnant women, so it has been excluded

Hui 2012 This is a randomised controlledtrial in Canada. The intervention aimed to explore the effect of an exercise and

dietary intervention on excessive gestation weight gain. The participants (n = 190) were non-diabetic pregnant

women (88 in the control group and 102 in the intervention group). Women of all BMI were recruited and

the results indicated that the intervention reduced excessive gestational weight gain. As the study did not aim

to reduce weight in obese pregnant women, it is excluded




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(Continued)

Jackson 2011 This is a randomised controlled trial including pregnant women of all BMI, recruited before 26 weeks of

pregnancy, n = 327 (163 in the intervention and 164 usual care). The study was conducted in the US.

The intervention was called ’Video Doctor’ - messages about diet, exercise and weight gain delivered by actor portrayed DVD delivered on a laptop in the clinic setting versus usual care. The primary outcome was

improvements in women’s diet and exercise behaviours, and weight gain was a secondary outcome. The results

indicate that there were statistically significant increases from baseline in exercise undertaken and consumption

of healthy foods, and significant decreases in unhealthy foods. There was no difference in weight gain between

the groups. The intervention did not aim to reduce weight in obese pregnant women and so has been excluded

Jeffries 2009 This is a randomised controlled trial including pregnant women of all BMI, recruited at 14 weeks of pregnancy,

n = 236 (46 of participants had BMI > 29 kg/m2). The study was conducted in Australia.The intervention

was a personalised weight measurement card and advice about optimal weight gain in pregnancy with advice

to self-record weight at 4 weekly intervals versus standard antenatal care. All women were weighed at 36 weeks

using the same hospital scale. Participants were blinded to the purpose of the study.The primary outcome was

weight gain from recruitment till 36 weeks of pregnancy. The results indicate that there was a trend of less

weight gain in the intervention group in all BMI categories of participants, except for those with a BMI >29 kg/m2. The intervention did not aim to reduce weight in obese pregnant women, but to reduce excessive

weight gain and so has been excluded

Koushkie 2003 This is a brief conference abstract describing a randomised controlled trial designed to assess the effect of an

aerobic exercise programme started in the third trimester on pregnancy outcomes. The participants were 26

pregnant women. It is not clear whether they were obese or not. The outcomes were gestational age, gestational

pregnancy weight gain, and changes in triceps skin thickness. The results indicate that there were no significant

differences between groups. No other publications related to this study have been found. The intervention did

not aim to reduce weight in obese pregnant women, and so has been excluded

Krummel 2009 This study was accessed from the ClinicalTrials.gov where it states that the trial started April 2009 in the US

(NCT00865683). The randomised trial will recruit pregnant women with a BMI greater than 25, however,

it is not clear how many are to be included in the study. The intervention is a nutritional supplement,

docosahexaenoic acid (DHA) versus placebo. The primary outcome is insulin sensitivity measured at month

3. Secondary outcome is interleukin - 6 (IL-6) measured at month 3. The authors have been emailed to find

out more about the study but no reply has been obtained. As the intervention is not designed to reduce weight

in obese pregnant women, the study is excluded

Lavender 2011 This is a pilot randomised controlled trial accessed from Current Controlled Trials (ISRCTN09432573). The

study was conducted in the UK. The intervention is a 10-week lifestyle programme incorporating behaviour

change theory versusroutine maternitycare.72 participants are to be recruited. The study is designed to explore

the feasibility and acceptability of the study, and the health of participants. Weight loss is not an outcome.

The intervention did not aim to reduce weight in obese pregnant women, and so has been excluded

Lombard 2011 This is brief conference abstract of a randomised controlled trial from Australia. The intervention was thedelivery of a self-management lifestyle plan with advice to self-weigh (n = 106). The control group (n = 99)

received normal advice about diet andexercise, and no recommendations to weigh themselves.The participants

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antenatal care interventin for reduce obese.pdf

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