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Background:  Increasingly HIV-infected women are embarking on more than 1 pregnancy. Cyclical use of ART predisposes to viral resistance and failure. Optimum management of sequential pregnancies is uncertain.

Methods:  HIV-infected women with more than 1 pregnancy since 1998 were examined. According to protocol, all women were offered antenatal ART and those with a pre-treatment CD4 > 300x10⁶/L discontinued therapy postpartum. When available genotypic resistance testing (HIV-1 TruGene) was performed after ART cessation postpartum.

Results:  Since the introduction of antenatal screening for HIV, 53 women have had more than 1 pregnancy:  43 had 2, 9 had 3, and 1 had 4, giving a total of 117 pregnancies. Of these women, 48 (90%) had acquired HIV heterosexually, 47(87%) came from Sub-Saharan Africa, and 37(79%) were originally diagnosed through antenatal screening. Vertical transmission occurred in 1 pregnancy and this was a first pregnancy. Of 117 women, 66 (56%) started ART in pregnancy and stopped postpartum (median pretreatment CD4 = 474x10⁶/L, viral load = 2989 copies/mL). Of these, triple-ART use increased with pregnancy number:  22 (63%) of first, 24 (96%) of second, and all of third pregnancies; 36 (55%) had postpartum genotypic data to guide subsequent ART prescribing, 20 (55%) no mutations, 2 (5%) primary reverse transcriptase mutations, and 14 (39%) unobtainable sequence or viral load < 500 copies/mL. Both mutations were seen after the first pregnancy. Median predelivery viral load was 50 copies/mL in the first pregnancy (n = 35), 50 copies/mL in the second (n = 25), and 147 copies/mL in the third (n = 4); 20 (57%) of first pregnancies and 16 (64%) of second had a viral load of < 50 copies/mL predelivery, in those with a a third pregnancy (n = 4) predelivery viral load was 65 copies/mL, 59,000 copies/mL (very late presentation), 50 copies/mL, and 230 copies/mL.    

Conclusions:  Vertical transmission of HIV did not increase with pregnancy number in this cohort. Despite stopping and starting ART, the proportion with virologic control increased between first and second pregnancy.

Keywords: HIV; pregnancy; antiretroviral therapy