In sub-Saharan Africa, women comprise approximately 60% of adults living with HIV [1] and there is evidence that pregnant women have a higher risk of acquiring HIV infection than non-pregnant women [2, 3]. Vertical transmission of HIV from mother-to-child remains a significant problem in the region; UNAIDS estimates that 390,000 children in sub-Saharan Africa were newly infected with HIV in 2008—around 90% of the global burden of new pediatric infections [4]. This situation persists despite the fact that antenatal HIV testing and prevention of mother-to-child-transmission (PMTCT) interventions can reduce vertical transmission of HIV to as low as 1–2% [5]. In many countries, HIV testing is now routinely included in antenatal care (ANC) services, unless the pregnant woman explicitly refuses it [6, 7]. The promise of antenatal HIV testing and PMTCT programs has led UNAIDS to call for a “virtual elimination” of mother-to-child transmission of HIV by 2015 [1]. However, several challenges remain to achieving successful implementation and scale-up of these services. Although ANC services are visited by the majority of pregnant women at least once during pregnancy, in 2008 only 28% of pregnant women in sub-Saharan Africa received an HIV test [1].