what’s new in obstetrics? dr clare tower mbchb phd mrcog consultant in obstetrics/ maternal and...
TRANSCRIPT
What’s new in Obstetrics?
Dr Clare Tower MBChB PhD MRCOGConsultant in Obstetrics/ Maternal and Fetal Medicine
Good Question!!
Obstetrics fairly low tech
Obstetric forceps invented in 1500s (!!)
Refined by William Smellie in the 1700s (lock and pelvic curve)
Remain largely the same today!
So what is new?
Antenatal
Intrapartum
Postnatal
Pre-conception Prevention
PreventionPrediction
ScreeningIntervention?
Prevention
Future health
Preconception
• Opportunity to optimise health before pregnancy as it improves pregnancy outcomes
• Most pregnancies are unplanned
• Should consider risk of pregnancy in ALL women of reproductive age with underlying medical problems.
General advice
• Rubella immunity• Diet• Smoking• Alcohol• Weight • Folic acid 400µg/ 5mg• Iron stores• Vitamin D deficiency
Medical disorders• Preconception counselling• Individualised• Refer to specific clinic• Aims to:
– Discuss risks of pregnancy– Risk of disease on pregnancy– Risks of pregnancy on disease– Risks and benefits of medications– Optimise disease control– Plans for conception and pregnancy
Stability
Don’t suddenly stop medication
Epilepsy
• Epilepsy is associated with maternal death• Anti-epileptic agents and epilepsy itself are
associated with fetal abnormality and child hood learning problems– Avoidance of valproate if possible
• Stability vital• Stable disease on lowest dose of fewest number of
drugs is the aim• DO NOT stop medications suddenly• 5mg Folic acid
Diabetes
• Commonest medical disorder in pregnancy (5% either GDM or pre-existing)
• Rising obesity = rising levels of type 2 diabetes• Rising numbers of women with gestational
diabetes– Some of these women have undiagnosed type 2
diabetes• Diabetes = increased risks in pregnancy
Diabetes (2)
• Fetal abnormality– Poor control (high blood sugar) = increased fetal
abnormality– HbA1C > 69-80mmol/mol (8.5-9.5%) in 1st 8 weeks
associated with malformation rates of up to 20%• Pregnancy complications
– Poor control increases risks of ALL complications– Pre eclampsia, miscarriage, growth restriction– Macrosomia, birth trauma,……
Diabetes Pre-con• Good control is
everything• Lower HBA1C to
43mmol/mol (6.1%), advise avoid if >86
• Discuss hypos• 5mg Folic acid• Refer early <10
weeks• Aspirin
• Drugs– ACE inhibs, ARBs, – statins
• Refer for pre-con if – End organ damaage– Brittle– Renal – Eye damage
SMH medical clinics
• Diabetic clinic• Renal hypertension clinic• Haematology clinic
– Bleeding/ clotting/ sickle• Cardiac clinic• Rheumatology clinic• Perinatal mental health• Neurology
• Obesity• (Teenagers)• Funded for Gastro
clinic
Miscarriage• Around 1:5 pregnancies end in miscarriage
– <10 weeks– Only 1-2% of second trimester losses miscarry before 24
weeks• Vast majority are sporadic and due to chromosomal
aneuploidies (nothing will affect this)• Risk of this increases with age:
– 20-24 yrs 11% miscarry– 30-34 yrs 15%– 35-39 years 25%– 40-44 years 51%– >44 years 93%
Recurrent miscarriage• 3 consecutive 1st trimester losses • Affects 1% of couples• Guidelines state that investigations should be
performed in the context of a specialist service
• Usually a recurrent miscarriage clinic• Generally only investigate after 3 miscarriages
in the 1st trimester…..
SMH RMC referral
• Women with recurrent miscarriage should be referral to the specialist clinic. Criteria for referral are as follows;
• 1) 3 or more consecutive first trimester miscarriages in women <35 years
• 2) 2 or more consecutive first trimester miscarriages in women >35 years or if miscarriage following IVF treatment
• 3) 1 or more miscarriage >12 weeks
Causes of recurrent miscarriage• Antiphospholipid syndrome (15%)• Chromosomal problems (balanced translocations in 1 partner
(rare)
• Vitamin D deficiency• Anatomical abnormality• Endocrine disorders (thyroid, uncontrol DM)• Coeliac disease• Shortened luteal phase• Other thrombophilias• Natural killer cells• Alcohol/ smoking/ obesity
Management of RM• Anxiety so need supportive care
– Associated with improved outcomes• ONLY proven (RCTs) treatment to date is aspirin and heparin
in women with antiphospholipid syndrome (15%) • Correct anatomical abnormality • Aspirin • Progesterone (luteal phase and 1st trimester- PROMISSE study)• Thyroxine• Prednisolone (NK cells)• GCSF – current trial• High dose folic acid (? Metafolate)
Screening for aneuploidy
• Increased risks of trisomy 21, 13 and 18 with maternal age
Age Risk T21 Key nos
20 1:1527 1:1500
30 1:895
35 1:356 1:350
40 1:97 1:100
42 1:55
Currently - • Problem: only way of providing a diagnosis is
amniocentesis or chorionic villus biopsy/ sampling (CVB/CVS)
• Risk of miscarriage:– Amniocentesis 1%
• done 15 weeks onwards
– CVS ?higher 1-2%• done from 11 weeks
Screening – which test?Test Measurements False +ve for 85%
detectionIntegrated test NT, PAPPA 10 weeks, AFP, E3 HCG
14-20 wks1.2%
Serum Integrated test As above no NT 2.7%
Combined test NT, PAPPA, HCG 10 wks 6.1%
Quadruple test AFP, E3, HCG, Inhibin A 14-20 wks 6.2%
Triple test AFP, E3, HCG 14-20 wks 9.3%
Double test AFP, HCG 14-20 wks 13.1%
Nuchal Translucency (NT) 12-13 weeks 20%
Screening for T21
• Offered to all women• High risk = greater than 1:150• Based arbitrarily on:
– Risk of miscarriage with invasive testing– Number of women likely to accept testing– Detection rate
• These women offered invasive testing• Choice is personal• Results: QF-PCR and full karyotype by culture
NIPT• Cell Free fetal DNA (non invasive prenatal
testing)• Proportion of cell free DNA in maternal
plasma is derived from the fetus• Amount increases with gestation (up to 50% in
later gestations)• Currently in clinical use for:
– Fetal sex determination (eg haemophilia from 11 weeks)
– Fetal blood type (eg Rhesus disease after 16 weeks)
Free fetal DNA and karyotype• Can a blood test be used to diagnose aneuploidy?
• Clinical use already in the UK for sex/blood group
• Uses chromosomal copy no T21, T18, T13
• MELISSA study (n=532): no false positives, high (97-100%) sensitivity and specificity for T21 T18 (lower for T13, 78%)
• Technology also being demonstrated for fetal genotype as well as karyotype
Clinical use• Technology exists – too expensive currently• Autumn 2011 – offered privately in the US• Sept 2012 – reported by British press• Available privately in the UK – costs around
£500-600, takes 2 weeks.• Reports as a risk (<1:10000) and fetal sex
NIPT and the NHS
• Not currently recommended • Too expensive but once cost falls to around £200/
test, will be economically viable• Likely to be offered along side current screening with
invasive testing to ‘positive’ women (or initially to ‘screen positive’)
• Concerns around limiting information to some women– Missing benefits from Nuchal screening?
Arrays
• CVS and amnio are tested for:• QF PCR – quantitative quick
way of looking for T21 T13 T18• Karyotype down a microscope
so low resolution• New technology is CGH array• Higher resolution• Too much information??
– Fine when you know postnatal outcome
– Difficult decisions antenatally
Aspirin• Low dose aspirin (75mg)• Meta – analysis has shown
that it reduces risk of pre-eclampsia/ growth restriction in women at high risk/ moderate risk
• RR PET 0.76 [95% CI, 0.62 to 0.95 , FGR 0.80 [CI, 0.65 to 0.99]
• Safe • From 12 weeks (probably
needs to be 8) to ? 36 weeks
Aspirin- for whom?• High risk:
– Previous hypertensive disorder of pregnancy– Renal disease– Autoimmune disease (APS SLE)
• Moderate risk (2 of these risks):– first pregnancy– age 40 years or older– pregnancy interval of more than 10 years– body mass index (BMI) of 35 kg/m2
or more at first visit– family history of pre-eclampsia– multiple pregnancy.
Ferritin levels
• Current NICE guidelines DON’T recommend routine iron supplementation OR ferritin testing
• St Mary’s test ferritin as part of Haemoglobinopathy screening on everyone
• So…. We can’t ignore it • If Ferritin is less than 30 – needs to be treated
Anaemia
• Very very common, predominantly Fe deficient• Women often enter pregnancy either anaemic or
with low iron stores– Menorrhagia– Short pregnancy spacing
• Defined as:– Hb <110g/l in first trimester, – <105g/l in second and third trimester– <100g/l in postpartum period
Management of anaemia
• Anaemia increases morbidity – Increase in poor neonatal outcomes– Increase in poor maternal outcomes (PPH)
• Management (BCSH):• Offer Fe supplements if ferritin <30 (200mg od) +
repeat Hb and ferritin in 8 weeks• If anaemic, BD or TDS iron supplemts, advise about
absorption• Once Hb is in the normal range supplementation
should continue for three months and at least until 6 weeks postpartum to replenish iron stores
Vitamin D and pregnancy
• Low vitamin D effects in pregnancy:– Increased risk miscarriage– Lower IVF success– Increased risks pre-eclampsia and placental
dysfunction• Low vitamin D effects on baby:
– Rickets, cardiomyopathy– Neonatal seizures– Breast feeding
Vitamin D
• Current NICE and RCOG guidelines do not recommend testing (? Will this change)
• All women should be offered 400IU (10mcg) vitamin D per day (healthy start vits if you can get them..)
• Recent RCOG scientific impact document suggests higher doses
RCOG Vit D
• Women at high risk of deficiency– Obese women, dark skinned, women who don’t
get much sun exposure, – 1000IU vit D per day– How to prescribe this as its not available on
prescription (!!)…..
• Women at high risk of pre-eclampsia– 800IU vit D + 1-1.5g calcium per day
Perinatal mental health
• In general, lowest dose and in monotherapy• Balance risks v benefits• Teratogenic risks difficult to define (remember
background abnormality rate is 3%)• All SSRIs have been associated with
abnormality in some studies and not in others• Paroxetine may increase the risk of
abnormality (especially cardiac) so avoid, especially 1st trimester (NICE 2007)
Late pregnancy SSRI
• Fluoxetine has lowest known risks in pregnancy
• SSRI after 20 weeks MAY be associated with pulmonary hypertension in neonate
• All can be associated with neonatal withdrawal (mild and self limiting)
• Citalopram and fluoxetine are present in breast milk at relatively high levels
Venous thromboembolism• Pregnancy associated with 10 fold increase in risk• Physiological changes in preparation for birth• Risks increased by (not exhaustive):
– Age - parity -multiple pregnancy– Obesity - mode of del - hospital admission
• No longer leading cause of death due to better management and prophylaxis
• Some women are offered LMWH antenatally purely because of risk factors
• Post natal treatment 1- 6 weeks
Delivery
• CS rate 21-22% (SMH)• National CS rate 25%
– Higher at some hospitals (30%)• Instrumental delivery rate 10-15%• Normal delivery rate around 60%
– 17-18% on midwifery led unit
Caesarean section
• What is the right Caesarean section rate?
Too posh to push???
Rates in USA 40-50%
Place of birth
• Most women give birth in hospital• Around 18-20% in alongside midwifery led
unit• Standalone unit only available to women with
a Salford post code (Salford)• Is it safe for women to give birth in their
home?
Place of birth
• Birthplace study (www.npeu.ox.ac.uk/birthplace/results)
• First baby:– Higher risks to baby (9.3
adverse perinatal outcome events per 1000 planned home births compared with 5.3 per 1000 births in obstetric unit)
– Transfer rate 45%• Second and subsequent
– No difference in perinatal outcome with home birth
– 10% transfer
Postnatal
• Hypertension in pregnancy (any)– At least double the risk of cardiovascular disease
• Diabetes in pregnancy– GDM– 50% risk of type 2 DM at 10 yearsEvents in pregnancy
predict the future
Opportunity for intervention
Postnatal management of Hypertension
• Women often discharged on anti-hypertensives• Keep systolic BP <160 mmHg• Expect rise in BP days 3-5• BP should be checked daily for 5 days post discharge,
see D/C letter for parameters to help with medication reduction (SMH)– 120/70/ stop– <130/80 reduce
• In women with pre-eclampsia, 6 weeks check to ensure proteinura resolved, if not refer to renal
Antihypertensives
• Antenatally usually labetalol and nifedipine• Post natally use medications that are once/
twice per day• Avoid methyldopa• Atenolol, nifedipine, amlodipine, doxazoscin
and ACE inhibitors all fine for breast feeding (avoid ACE if baby v preterm as risk of hypotension)
• Annual check and modification of life style factors
Gestational DM
• Risk of underlying type 2 diabetes• All women should be checked for this
postnatally• Current NICE guidelines
– 6 week glucose tolerance OR– 3 month HbA1C/ fasting plasma glucose
• Compliance!!• Annual screening
Summary• Pregnancy is a massive screening
exercise
• Optimisation of health improves outcomes
• Complications in pregnancy act as a crystal ball for the future