Research in context
Evidence before this study
A systematic review and meta-analysis on perinatal outcomes associated with maternal HIV infection was published in 1998. Only publications up to 1996 were included, many of which were abstracts. The perinatal outcomes were poorly or not defined, gestational age estimation methods were not assessed, and a fixed-effects model was used to pool the data despite substantial between-study heterogeneity.
Added value of this study
We have done a systematic review and meta-analysis including studies published up to 2014, at a stage in the epidemic when an increasing number of pregnant women worldwide are receiving antiretroviral therapy, making the likelihood of new evidence emerging in the future low. Perinatal outcomes were clearly defined a priori, inclusion and exclusion criteria were strictly applied to reduce bias, and a random-effects model was used to pool the data. Our study shows that antiretroviral therapy-naive maternal HIV infection is strongly associated with increased risks of preterm birth, low birthweight, small for gestational age, and stillbirth, and weakly associated with term low birthweight and preterm low birthweight. The evidence did not support an effect on very preterm birth, very low birthweight, very small for gestational age, miscarriage, or neonatal death.
Implications of all the available evidence
The evidence for an association of maternal HIV infection with adverse perinatal outcomes is strongest and most consistent in sub-Saharan Africa, the region with the highest burden of maternal HIV infection. Antiretroviral therapy reduces maternal morbidity and mortality and greatly reduces mother-to-child transmission of HIV, but the effect of different antiretroviral therapy regimens on perinatal outcomes is unknown. WHO recommends triple-drug antiretroviral therapy regimens during pregnancy for all HIV-positive women and lifelong treatment thereafter. With continued expansion of treatment programmes, especially in sub-Saharan Africa, an urgent need exists to assess the effect of antenatal antiretroviral therapy regimens on perinatal outcomes.