Pregnancy outcomes in women exposed to efavirenz and nevirapine in Cote dIvoire
Polly Clayden, HIV i-Base
Another report, this time by Didier Ekouevi and colleages in the 1st February issues of JAIDS, shows no increased risk of adverse outcomes in infants exposed to maternal efavirenz (EFV) in pregnancy. 
Although a retrospective analysis, this study, conducted in Cote dIvoire, is the largest to date looking at pregnancy outcomes following first trimester EFV exposure.
It was conducted in Abidjan across four centres participating in the International epidemiological Databases to Evaluate AIDS (IeDEA) West Africa and in two ANRS trials.
The investigators searched the trial databases and the computerised information systems from the participating centres. Women who conceived receiving EFV or nevirapine (NVP) between January 2003 and July 2009 were included.
Five outcomes were evaluated:
- Abortion, defined as voluntary termination of pregnancy.
- Miscarriage <20 weeks gestation.
- Stillborn, between 20 weeks and delivery.
- Preterm delivery (PTD) <37 weeks and low birth weight (LBW) <2500 grams.
- Congenital abnormalities observed in the first six weeks of age.
A total of 344 women met the study criteria. Of these, 213 (61.9%) conceived while on EFV-based HAART and 131 (38.1%) while on NVP-based HAART. Their median age at initiation of treatment was 29 (IQR 26-32) years; CD4 count 217 (IQR 146-280) cells/mm3 and just over half were WHO stage 3 or 4.
Nucleoside backbones were d4T/3TC, AZT/3TC, ddI/d4T or TDF/FTC. Baseline characteristics were similar for women receiving EFV or NVP except that more women received AZT/3TC with EFV than NVP, p<0.001.
Similar proportion of women in both groups were lost to follow up during pregnancy: 4.7 vs 6.1% in the EFV and NVP arms respectively, p=0.57. The majority of women (190/213, 89.2%) switched to either a PI or NVP when they found they were pregnant. Two women that conceived while receiving NVP switched to a PI due to side effects. The median duration of exposure after conception was 52 (IQR 37-75) days in the EFV group and 264 (IQR 222-285) days in the EFV group, p<0.001.
The investigators found, of the 203 women in the EFV group and 123 exposed to NVP for whom pregnancy outcome was known, there were no statistical differences in incidence of miscarriage or stillbirth among the two groups; 5.2% and 6.7% respectively overall. However the proportion of women having an abortion was greater in the EFV group than the NVP group, 14.3 vs 7.3%, p=0.05.
Birth weight data were available for 223 (89.6%) infants who had a median birth weight of 2800 (IQR 2500-3250) grams. PTD occurred in 27 (10.8%) infants, 9.5 vs 12.7% in the EFV and NVP groups respectively, p=0.76. LBW occurred in 45 (20.2%) infants, 17.2 vs 24.2%, p=0.2. No abnormalities were observed in infants exposed to either EFV or NVP, upper limits of 95% CI, 2.5% and 3.6% respectively.
This study needs no new comments to those previously reported on this subject, with an acknowledgement of the limitations of retrospective analyses.
These data were included in the meta-analysis looking at birth outcomes following EFV exposure by Ford et al. 
Once again, there is a high rate of voluntary abortion, which may be explained by health workers attitude to EFV in pregnancy.
- Ekouevi D et al. Pregnancy outcomes in women exposed to efavirenz and nevirapine: an appraisal of the IeDEA West Africa and ANRS databases, Abidjin, Cote dIvoire. J Acquir Immune Defic Syndr. Volume 56, Number 2. February 1, 2011.
- Ford N et al. Safety of efavirenz in first trimester of pregnancy: a systematic review and meta-analysis of outcomes from observational cohorts. AIDS 2010. Published ahead of print May 24, 2010.