Advances in evidence-based antenatal care

David EllwoodProfessor of Obstetrics & Gynaecology

Primary Care Network, UQCCR, 28th August 2013

Numbers of births

Primary Care Network, UQCCR, 28th August 2013

Maternal age in 2010 Median age of all mothers was 30 yrs 3.9% of mothers were <20 23.0% of mothers were over 35 4.1% were over 40 Significant increase in the proportion of

mothers >35 over last 20 years

Primary Care Network, UQCCR, 28th August 2013

Changes in first-time mothers

Primary Care Network, UQCCR, 28th August 2013

Primary Care Network, UQCCR, 28th August 2013

‘The most significant reproductive threat of modern times has to be the overweight & obesity epidemic’

Overweight & obesity Major risk factor which impacts on all types of

adverse outcome in pregnancy & birth No national data previously reported Only 5 jurisdictions were able to provide data on

BMI at booking for the 2010 collection» 49.9% had a booking BMI of >25» 22.4% were >30 (obese)» Approximately 4% have BMI >40 (ACT data)» 3 per 1000 have BMI >50 (AMOSS)

Primary Care Network, UQCCR, 28th August 2013

Smoking in pregnancy Data quality is variable but has

been improving over time All states & territories submitted

data in 2010 Overall rate was 13.5% (cf. 16.2%

in 2007)» Rates vary from 11.2% (NSW &

ACT) to 25.5% (TAS)» 36.7% of teenage mothers

admitted smoking in pregnancy (cf. 39% in 2007)

Primary Care Network, UQCCR, 28th August 2013

Key points about ANC Antenatal care is an intervention that is used for over

300,000 women each year in Australia There are a number of important elements

» screening for maternal and fetal health» education and access to information» emotional and psychological support

Antenatal care is delivered in many different settings and by as variety of health care professionals

It is expensive, and until recently, there were no national guidelines which are evidence-based

Primary Care Network, UQCCR, 28th August 2013

Cost estimates for ANC? 300,000 women per year in Australia 10 visits each ($50-70 each) Antenatal investigations ($200-300) Ultrasounds x 2 ($140-500) These estimates vary from $250M to 450M per

annum across Australia

Primary Care Network, UQCCR, 28th August 2013

Evidence-based Antenatal Care

Clinical Practice Guidelines

Antenatal care – module 1

Published in 2012 (Co-Chairs: Professors Caroline Homer & Jeremy Oats)

Primary Care Network, UQCCR, 28th August 2013

Grades of EvidenceGrade A: Body of evidence can be trusted to guide practice

Grade B: Body of evidence can be trusted to guide practice in most situations

Grade C: Body of evidence provides some support for recommendations but care should be taken in its application

Grade D: Body of evidence is weak and recommendation must be applied with caution

CBR: Recommendation formulated in the absence of quality evidence

PP: Area is beyond the scope of the systematic literature review and advice was developed by the EAC and/or the Working Group for Aboriginal and Torres Strait Islander Women’s Antenatal Care

Primary Care Network, UQCCR, 28th August 2013

Evidence-based antenatal investigations

First trimester (Maternal Health Screening)» Ultrasound (8 to 14 weeks) for those who are uncertain of

their conception date (B)» Asymptomatic bacteruria testing early in pregnancy (A)» Vitamin D screening to those with risk factors (CBR)» Give information about testing for chromosome abnormalities

Primary Care Network, UQCCR, 28th August 2013

Antenatal Investigations (2) Recommended infection screens

HIV testing at first antenatal visit (B) Hepatitis B testing (A) Hepatitis C only for those with identifiable risk factors (C) Syphilis testing at first antenatal visit (B) Rubella immunity (B) Chlamydia for women under 25 (C)

Primary Care Network, UQCCR, 28th August 2013

Nutritional supplements in pregnancy Folic Acid (500 micrograms per day) from 12 weeks

before until 12 weeks after conception (A) No benefit in taking Vitamins A, C or E supplements

and may cause harm (B) Iodine supplementation (150 micrograms per day) for

all pregnant women (CBR) No routine iron supplementation (B)

Primary Care Network, UQCCR, 28th August 2013

Two recent and controversial aspects Screening and/or testing for chromosomal

abnormalities Screening for gestational diabetes

(Both of these are significantly age-related….)

Primary Care Network, UQCCR, 28th August 2013

Screening for Chromosomal Abnormalities Combined 1st trimester screening (nuchal

translucency & PAPP-A/HCG) has been a successful program for 10-15 years

It is safe, effective, and acceptable to most women Advantages

» relatively inexpensive ($100-150)» high detection rate (93 to 95%)

Disadvantages» high screen positive rate (5%)» diagnostic test is invasive» hard to understand (adjusted risk)

Primary Care Network, UQCCR, 28th August 2013

Non-invasive fetal testing Fetal DNA from the maternal circulation can now be

used to diagnose fetal aneuploidy (although current approach is to confirm with CVS or amniocentesis)

Detection rates for T21, T18 and 13, and sex chromosome aneuploidy are > 99%

But is this an improvement on the current approach? How should it be judged?

» effectiveness» cost» acceptability

Primary Care Network, UQCCR, 28th August 2013

Options for screening/diagnosis of T21

1. Continue with current approach of NT/SS followed by CVS or amniocentesis

2. NT/SS followed by NIFT for those who are screen positive

3. NT/SS for low risk women and NIFT for high risk

(a) > 35 years (23%)

(b) > 40 years (4%)

4. NIFT for all women who want it

(and can afford to pay for it…)

Primary Care Network, UQCCR, 28th August 2013

Cost comparisons for different DS approaches

Primary Care Network, UQCCR, 28th August 2013

    Model 1 Model 2 Model 3.A Model 3.B Model 4

  No. of DS detected in 100,000 women (220)

205 203 214 214 218

  Procedure-related losses 34 2 27 33 3

Low Cost          

  Total cost ($) 13,780,250 14,121,486 26,822,321 16,174,482 70,144,326

  Cost per person ($) 139 141 268 162 701

  Cost per DS detected ($) 67,221 69,564 125,338 75,582 321,763

High Cost          

  Total cost ($) 48,250,000 47,439,200 67,291,100 51,795,030 136,461,100

  Cost per person ($) 482 478 673 518 1,364

  Cost per DS detected ($) 235,826 235,537 314,458 242,033 625,968

Which way to choose? Using NIPT alone will maximise the diagnoses of DS, reduce the

overall procedure-related loss rate, but is extremely expensive Using NIPT as a ‘second screen’ reduces the numbers of

CVS/amniocenteses performed (and therefore the procedure –related losses) but does add time to the process

The most cost-effective approach is using NIPT only for those who are very high risk and are likely to need invasive testing regardless of the screening result

If NIPT could be accepted as the diagnostic test as well this would eliminate the need for CVS or amniocentesis

If the cost of NIPT reduced to about $150 per patient it would be cost-comparable, with the highest detection rate and virtually no procedure-related losses

Primary Care Network, UQCCR, 28th August 2013

Screening for Gestational Diabetes Current approach is 50g glucose load for all women,

with 75g GTT for screen +ve women (>7.8mmol/L) Recent recommendations from ADIPS are;

» 75g GTT for all & early testing (as soon as possible after conception) for high risk women

» No need for 3 day CH20 dietary loading

» Change criteria for diagnosis of GDM; Fasting BSL reduced to 5.0mmo;/L Add a 1 hour criterion (>10.0mmol/L) Increase the 2 hour cut-off to 8.5mmol/L

Primary Care Network, UQCCR, 28th August 2013

Problems with these changes This will lead to an increase in the number of cases of

GDM diagnosed, and therefore increased numbers who need to be managed by a multi-disciplinary team

Compliance is a problem with the current approach so it is likely that this will reduce further

Unknown fetal effects of treating more women with insulin from earlier in pregnancy

There has been no rigorous cost-benefit analysis to support this change

Primary Care Network, UQCCR, 28th August 2013

CONCLUSIONS Antenatal care now has a rigorous, evidence-based

guideline Unfortunately, much of the evidence for some of the

recommendations is quite poor Antenatal care is very expensive, and it is important

that cost-benefit analyses are done to inform best practice

Primary Care Network, UQCCR, 28th August 2013