Optimizing PMTCT efforts by repeat HIV testing during antenatal and perinatal care in resource-limited settings: A longitudinal assessment of HIV seroconversion

BACKGROUND: Mother to child transmission (MTCT) of HIV remains a challenge in resource-limited settings. Central to elimination of MTCT is effective Provider Initiated HIV Counseling and Testing (PICT). Research has shown that conducting PICT only at the initial antenatal care (ANC) visit fails to benefit pregnant women who seroconvert later in their pregnancy. This study aimed to determine the most cost effective time to perform repeat HIV testing during ANC and perinatal care (PNC). METHODS: We studied the repeat HIV testing results of pregnant women ≥ 18 and adolescent girls aged 15-17 in the Sauri, Kenya Millennium Villages Project (MVP) site. Nurses provided HIV screening to 1,403 expectant women and 256 adolescent girls following the 1st, 2nd, 3rd and 4th ANC visits, at birth and 6 and 14 weeks postpartum. RESULTS: Five women seroconverted during the study period (incidence proportion 0.41%). One woman seroconverted at the 2nd ANC visit, another one at the 3rd, two at the 4th and one at 6 weeks post-partum. Of all the women who seroconverted, four reported an HIV negative primary partner, while one reported an unknown partner status. None of the participants reported condom use during pregnancy. Two of the seroconverters vertically transmitted HIV to their babies. The results did not suggest a clear pattern of seroconversion during ANC and PNC. CONCLUSIONS: The low rates of seroconversion suggest that testing pregnant women multiple times during ANC and PNC may not be cost effective, but a follow-up test during birth may be protective of the newborn.