Other studies looking at birth outcomes
Polly Clayden, HIV i-Base
Two posters looked at incidence of low birth weight and preterm birth in infants born to women receiving HAART.
Didier Koumavi Ekouevi and coworkers reported findings from an analysis of pregnancy outcomes in Ditrame Plus/MTCT Plus, Abidjan. 
Women in this study received either a PMTCT regimen of short-course AZT plus single dose NVP or short course AZT/3TC plus single dose NVP (n190) or NVP-based HAART of AZT or d4T/3TC/NVP (n=168). All women in the ART group initiated treatment at least 28 days before delivery. The study evaluated the following: low birth weight (<2500 g), stillbirth, and neonatal mortality. Only singleton births were included.
The investigators reported no difference between the rate of stillbirths in the HAART group and the PMTCT group: 3.1% vs 2.9% respectively, p=0.85. There was a significant difference between the rate of low birth weight: 22.3% in the HAART group and 12.4% in the PMTCT group (p=0.02).
In a multivariate analysis (n=309), they found HAART was independently associated with low birth weight (OR 2.53, 95% confidence interval 1.20 to 5.35; p=0.015) after adjusting for CD4 count, WHO staging, maternal age, and maternal body mass index.
They found the 1-month probability of survival in HIV-positive infants was not statically different in those with and without low birth weight (94.3% vs 98.8, p=0.13).
They concluded: ART initiated in pregnant women with advanced disease who are eligible for ART is associated with low birth weight. The relationship between maternal ART with advanced disease and infant outcomes, including child survival, requires further study.
Kisumu Breastfeeding Study (KiBS)
The Kisumu Breastfeeding Study (KiBS), is a phase IIB single-arm study evaluating maternal HAART for PMTCT in breastfeeding mothers in Kenya.
Rose Masaba and coworkers reported findings from analysis comparing rates of premature births and low birth weights among ARV-naive HIV-positive pregnant women receiving different ARV regimens. 
Women in KiBs received either AZT/3TC/NVP or AZT/3TC/NFV from 34 weeks gestation to 6 months post partum. In this study preterm delivery was defined as <37 weeks) and low birth weight as <2500g).
Of 403 women with CD4 >/=250 cells/mm3 196(48%) received a NVP-based regimen and 207 (52%) received a NFV-based regimen. After 20 women withdrew from the study. Of 383 remaining women there were 384 (98%) were live births and 7 (2%) stillbirths.
The median duration of antenatal exposure to NVP was 5.1 weeks (Range 0.29 to 11.6) was lower than NFV, 6.0 weeks (Range 0.57 to 12.2) p=0.008. Of the live infants, 65 (17%) were preterm and 51 (13.3%) were of low birth weight.
The investigators reported, after controlling for baseline maternal viral load and duration on HAART before delivery, the rate of preterm deliveries was not significantly different between the two treatment groups: 19% vs 14% for those on NVP and NFV, respectively p=0.08. Nor did they find a difference in the rate of low birth weight: 14% vs 12% for NVP and NFV, respectively, p=0.7.
The investigators recommended: Assessment of other safety features and tolerance should also be used to guide choice of NVP or NFV in PMTCT ARV regimens.
A lack of effect of HAART on preterm delivery when it is started as late as 34 weeks is not really very surprising.
Not estimating gestational age at delivery to try to explain why babies have small birth weight when exposed to HAART from 28 weeks is.
- Koumavi Ekouevi D, Tonwe-Gold B, R Becquet R et al. Low birth weight with nevirapine-based ART in Abidjan, Cote d’Ivoire: The ANRS Ditrame Plus Cohort and MTCT-Plus Initiative, 2001 to 2007. 15th CROI. February 2008. Boston USA. Poster abstract 641.
- Masaba R, Ndivo R, Nyangau I et al. Comparison of adverse foetal outcomes in HIV-1-infected antiretroviral-naive pregnant women who have received combivir and either nevirapine or nelfinavir for prevention of mother-to-child transmission antenatally 15th CROI. February 2008. Boston USA. Poster abstract 640.