Indian J Pediatr 1993; 60 : 269-274

Maternal Risk Factors Associated with Low Birth Weight

Nurul Amin, R. Abel and V. Sampathkumar

RUHSA Department, Christian Medical College & Hospital, North Arcot Ambedkar District, Tamil Nadu

Abstract. Maternal factors comprising of social, obstetric and anthropometric are fund to influ- ence LBW. The present study had found association between obstetric risk factors like age of the mother, parity and gravida with LBW. Similar association was also observed between ma- ternal height, and maternal weight with LBW. However, social factors were not found to be associated with LBW. This could probably be due to RUHSA's intervention which requires a further inquiry. (Indian J Pediatr 1993; 60 : 269-274)

Key words: Low birth weight; Normal birth weight; Maternal factors; Social factors.

T he increasing concern on low birth weight (LBW) have prompted many

workers to look into the factors associ- ated with LBW. LBW is found to be one of the major causes of high mortality and morbidity rates. 1 LBW may indicate that the baby did not remain in utero long enough, or it did not develop well enough. 2 A multi-factorial inter-relation- ship exists between the environment in which pregnant mothers live and the growth of the fetus? Among the factors that were postulated to have an effect on LBW, maternal factors were found to be more prominent. 4 Several studies have recorded the relationship between ma- ternal age, 3'sf'': parity, 3'6'7 pre-pregnancy weight a,9 and education of mother -a with LBW. But it is not clear as to whether all of these maternal factors are universal. In one study, maternal age was found to

Reprint requests : Dr. Rajaratnam Abel, Ru- ral Unit for Health and Social Affairs Depart- ment, Christian Medical College and Hospi- tal, RUHSA Campus, P.O. 632 209, North Arcot Ambedkar District, Tamil Nadu,

have no effect on LBW. I~ The purpose of this study was to identify not only the relationship of social and obstetric r i sk factors of the mother with LBW, but also the relationship of maternal anthropom- etric factors like height and weight with LBW.

MATERIAL AND METHODS

Study Population Design

The present study was carried out in the rural villages of K.V. Kuppam block of Tamilnadu in Southern India. A primary health care intervention programme is being implemented by RUSHA* Depart- ment of Christian Medical College and Hospital since 1977.11

The design of this study involves a case control approach. Mothers who de- livered LBW infants were the cases, and mothers who delivered normal birth weight (NBW) infants were the controls.

From the birth weight monitoring rec- ords a list of LBW and NBW infants was obtained for the period 1990-91. All the

270 THE INDIAN JOUILNA L OF PEDIATRICS

53 LBW mothers available till date, and 49 NBW mothers rendomlly picked were included in this study.

M e a s u r e m e n t s

Data on maternal age, education, caste, type of roof, parity, and gravida was col- lected with the help of a structured inter- view schedule. Height was measured with the help of a Somatometer (Stanley mobo 01-116 microtoise)nailed to a wall, and the value was recorded to the near- est 0.1 cm. A second measurement was taken randomly to check for accuracy. Weight was measured with the help of a bathroom weighing scale (Krupps model), and the value was recorded to the nearest 10 grams. A second measure- ment was taken randomly to check for accuracy. The weighing scale caliberated against standard weights at the end of the day. BMI was calculated using height and weight data obtained. Statistical tests like chi-square and odds ratio were used in the analysis.

RESULTS

This study is based on the analysis of 53 LBW mothers and 49 NBW mothers. Table 1 shows the distribution of mater- nal factors like age, education, caste, type of roof, parity, gravida, height and BMI according to LBW and NBW. Among the mothers who were aged 20 years and below, 67% delivered LBW babies while of the mothers who were aged more than 20 years, only 46.7% had delivered LBW babies. The odds ratio calculation for this table was 2.28, which indicates that mothers who were 20 years and below had that many times the

1993; Vol. 60. No. 2

risk of delivering LBW babies. Around 50% of the mothers in each educational level were fund to deliver LBW babies, indicating no effect of mothers ' educa- tion on LBW. Tile percentage of sched- uled caste mothers who delivered LBW was 47.1%, which was less when com- pared to mothers of other castes who de- livered LBW babies (54.4%). The odds ratio was 0.75. Data on type of roof was collected as this serves as a proxy to so- cio-economic status. However, in the present study, 58.6% of the mothers who lived in tiled houses del ivered LBW babies, which was higher than mothers who lived in thatched houses (49.0%), and terraced houses (50.0%). The asso-

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�9 LB~%

[ ] N B ~

80q -

60% -

40%

20%

0% ,:35 35-44 45-54 > 55

Maternal ~ei~ht cKg~

Fi 8. 1. Relationship between maternal weight and birth weight. LBW : Low Birth Weight NBW : Normal Birth Weight Kg : Kilogram

1993; Vol. (~J. No. 2 THE INDIAN JOURNAL OF PEDIATRICS 271

100%80 % I []�9 NB~'~LB~

O0 e,c "--

40 %

. /

I 2 3 Parity

Fi8.2. Relationship between parity and birth weight LBW : Low Birth Weight NBW : Normal Birth Weight 1, 2, 3, 4 represents parity 1, parity 2, parity 3 & parity 4

ciatk,n was statistically not significant. Between gravida and birth weight, 70% of the mothers who were gravida, one delivered LBW baby, while only 59.0% of gravida two and 32.5% of gravida three and above delivered LBW babies. This was statistically significant (p>0.01). As regards maternal height, 61.7% moth- ers with height less than 150 cm deliv- ered LBW babies when compared to 43.6% mothers with height >. 150 cm who delivered LBW babies. This was statisti- cally not significant. The odds ratio was 2.09. Body mass index (BMI) calculation showed that mothers with less than 18.5 BMI delivered more number of LBW

babies (56.9%), than mothers with BMI 18.5 and above (47.1%). The odds ratio was 1.48.

Figure 1 depicts the relationship be- tween maternal weight and birth weight. A statistically significant association was observed between maternal weight and birth weight (p<0.O01).

The relationship between parity and birth weight is shown in Figure 2. The association between parity and birth weight was statistically significant (p<0.001).

DISCUSSION

The results of the present study have in- dicated that there is a definite associa- tion between maternal factors and birth weight. Maternal age was found to have an association with LBW. Young moth- ers (<20 years) were found to deliver more number of LBW babies. These re- sults corroborate findings from other studies. 3's,7.7 However one study failed to observe this relationship, where no dif- ferences in birth weight was observed between babies delivered by adolescent mothers, and babies delivered by young primi gravda mothers. 1~ Previous studies had reported the association between mothers educational status and birth weight, with a lower percentage of LBW babies delivered by educated mother. -~ The present study failed to produce this association. A reason that can possibly be attributed to this could be the effec- tive primary health care intervention programme by RUHSA Department of Christian Medical College and Hospital. This could have diffused the differences which are usually noted among people with different socio-economic back-

272 THE INDIAN JOUbhNAL OF PEDIATRICS 1993; Vol. 60. No. 2

Table 1. Distribution of Maternal Factors According to LBW and NBW

LBW NBW Total (<2.5 kg) (>2.5 kg)

No % No % No %

Maternal age <20 (yrs) >20

Moher's education No education 1-5th standard 6-10th standard

Caste Scheduled caste Other castes

Type of Roof Thatched Tiled Terraced

Gravi& One Two Three & above

Maternal height <150 >150

BMI Status <18.5 >18.5

18 67.0 9 33.0 27 100.0 35 46.7 40 53.3 75 100.0

17 53.0 15 47.0 32.0 100.0 13 54.0 11 46.0 24 100.0 23 50.0 23 50.0 46 100.0

16 47.1 18 52.9 34 100.0 37 54.4 31 45.6 68 100.0

24 49.0 25 51.0 49 100.0 17 58.6 12 41.4 29 100.0 12 50.0 12 50.0 24 100.0

23 70.0 10 30.0 33 100.0 17 59.0 12 41.0 29 100.0 13 32.5 27 67.5 40 100.0

29 61.7 18 38.3 47 100.0 24 43.6 31 56.4 55 100.0

29 56.9 22 43.1 51 100.0 24 47.1 27 52.9 51 100.0

ground in other areas. Moreover , a con- certed effort is being put in to serve the most depr ived people in this region. This is fur ther s t rengthened by tile finding of lower LBW rates a m o n g scheduled castes. Similarly the effect of type of roof on birth weight was not observed .Type of roof is taken as a proxy for socio-eco- nomic status. LBW babies was higher a m o n g mothe r s who lived in tiled houses , than terraced and tha tched

houses. Pari ty was found to be signifi- cant ly (p<.001) associa ted wi th bi r th weight. The percentage of LBW babies was high among primigravid mothers. This was also repor ted by Schelp et al, 1 where they found higher rates of LBW among pr imigravida mothers. No statis- tically significant relationship was ob- served be tween height and birth weight. Mothers with height less than 150 cm del ivered more number of LBW babies.

1993; Vol. 60. No. 2 THE INDIAN JOURNAL OF PEDIATI~,ICS 273

Isabelle et al 1~ found no significant asso- ciation between materna l height and birth weight. On the other hand, Kraemer 4 in his widely reviewed article quoted from several studies reported a significant association between maternal height and birth weight.

When a BMI calculation was done, LBW rates were found to be slightly higher among mothers with BMI<18.5 than mothers with BMI > 18.5. Mothers with BMI less than 18.5 indicates chronic energy deficiency. 12 Several studies had shown a statistically significant associa- tion between maternal weight and birth weight. 8.9.1~ The present s tudy also had shown a statistically significant relation- ship between the two variables (p<0.001). LBW rate was high among mothers with weight less than 35 kgs and weight less than 45 kgs. Just as ma- ternal weight, parity was also signifi- cantly associated wi th birth weight. Primipara mothers (parity one) deliv- ered more number of LBW babies than parity two, three, and four and above. This was reported by other studies also. 3,6 However, Leo et al s found higher rates of LBW among mothers with parity 3 and above.

In summary, our findings had shown a significant relationship between mater- nal factors and birth weight. The finding that education of the mother, caste and type of roof had no bearing on birth weight reveals that an effective health and deve lopmen t p r o g r a m m e may probably ward of the influences of poor socio-economic status on various health parameters. Despite the limitation of the small sample size, the s tudy results have shown several leads. Further longitudi- nal birth weight monitoring and mater-

hal a n t h r o p o me t r y moni to r ing pro- gramme, both hospital based and com- muni ty based are being currently carried out.

REFERENCES

1. Schelp FP, Pongpaew P. Analysis of low birth weight rates and associated factors in a rural and an urban hospital in Thailand. J. Trop Pediatr 1985; 31 : 5-8.

2. Ghosh S, Bhargava SK, Madhavan S et al. Intra-uterine growth of North Indian babies. Pediatrics 1971; 47 : 826-830.

3. Makhijak, Murthy GVS, Kapoor SK, Lobo J. Socio-biological determinants of birth weight. Indian J Pediatr 1989; 56 : 639-643.

4. Kraemer MS. Determinants of delivering low birth weight: Methodological assess- ment and meta analysis. Bull WHO Org 1987; 65: 663-737.

5. Elster AB. The effect of maternal age, parity and prenatal care on perinata] out- come in adole~ent mothers. Am ] Obstet Gynecol 1984; 149 : 845-847.

6. Lee K, Ferguson RM, Corpuz M e t al. Maternal age and incidence of low birth weight at term: A population study. Am J Obstet Gynecol 1988; 158 : 84-89.

7. Kumari S, Shendurnikar N, Jain Se t al. Outcomes of low birth weight babies with special reference to some maternal factors. Indian Pediatr 1989; 26 : 241-245.

8. Moller B, Medhin M, Lindmark G. Mate- nal weight, weight gain and birth weight at term in rural Tanzanian village of Ilula. Br J Obstet Gynecol 1989; 96 : 158- 166.

9. Lawoyin TO. maternal weight and weight gain in Africans. Is relationship to birth weight. J. Trop Pediatr 1991; 37 : 166-171.

10. Horon IL, Strobino DM, Mac Donald HM. Birth weights among infants born to

274 THE INDIAN JOURNAL OF PEDIATRICS

adolescent and young adult women. ,'ltn J Obstet Gyllecol 1983; 146 : 444-449.

11. Abel R. RUHSA - A model pr imary

1993; Vol. 60. No. 2

health care. Trop Pediatr. (In Press). 12. Nutrit ion News. National Institute of

Nutrition. Hyderabad 191; 12(2).

STRATEGIES FOR CONTROLLING MICRONUTRIENT MALNUTRITION

Twenty percent of the world's people are at risk for micronutrient malnutrition (iron, vitamin A and iodine), and they are concentrated in developing countries. Effective control strategies have been proposed for each micronutrient deficiency, but the opportunity for coordinating these strategies has not yet been fully explored.

Several opportunities for multiple fortification exist :

* Double fortification of salt with iron and iodine. * Fortification of processed rice with vitamin A and iron. * Fortification of sugar with vitamin A and iron. * Multiple fortification of widely consumed speciality foods, citrus drinks for school

children, soft drinks, cookies, and nutricubes

Fortification of salt with iodine has been successful and should be expanded to all countries where deficiency exists. Fortification levels, which depend on per capita consumption of salt and anticipated storage losses, range from 20 to 100 parts per million. Potassium iodate is the preferred additive because it is more stable than other compounds.

Fortification of foods with iron is much more complex than fortification of salt with iodine because variations in dietary absorption and dietary patterns in different countries influence iron availability. In addition, because the required dosage of iron is at least 50 times more than the required dosage of iodine, taste and color changes occur in some iron fortified foods.

Iron EDTA is a promising fortificant. Because it is absorbed much better than other fortificants, smaller amounts can be used, and color and taste are mere acceptable. Use of iron EDTA in countries with a high prevalence of nutritional anemia seems desirable.

Vehicles used for vitamin A fortification include sugar, rice, and some speciality foods. The workshop participants were intrigued by the idea of fortifying and reprocessing broken grains of rice. This process may enable the development of a premix that would permit control of color and stability, and would allow fortification with iron as well as vitamin A.

Abstracted From : Coordinated Strategies For Controlling Micronutrient Malnutrition : A Technical Workshop.