Prevalence and determinants of unplanned pregnancy in HIV-positive and HIV-negative pregnant women in Cape Town, South Africa: a cross-sectional study.

Objectives: Prevention of unplanned pregnancy is a crucial aspect of preventing mother-to-child HIV transmission. There are few data investigating how HIV status and use of antiretroviral therapy (ART) may influence pregnancy planning in high HIV burden settings. Our objective was to examine the prevalence and determinants of unplanned pregnancy among HIV-positive and HIV-negative women in Cape Town, South Africa.

Design: Cross-sectional analysis.

Settings: Single primary-level antenatal care clinic in Cape Town, South Africa.

Participants: HIV-positive and HIV-negative pregnant women, booking for antenatal care from March 2013 to August 2015, were included.

Main Outcome Measures: Unplanned pregnancy was measured at the first antenatal care visit using the London Measure of Unplanned Pregnancy (LMUP). Analyses examined LMUP scores across four groups of participants defined by their HIV status, awareness of their HIV status prior to the current pregnancy and/or whether they were using antiretroviral therapy (ART) prior to the current pregnancy.

Results: Among 2105 pregnant women (1512 HIV positive; 593 HIV negative), median age was 28 years, 43% were married/cohabiting and 20% were nulliparous. Levels of unplanned pregnancy were significantly higher in HIV-positive versus HIV-negative women (50% vs 33%, p<0.001); and highest in women who were known HIV positive but not on ART (53%). After adjusting for age, parity and marital status, unplanned pregnancy was most common among women newly diagnosed and women who were known HIV positive but not on ART (compared with HIV-negative women, adjusted OR (aOR): 1.43; 95% CI 1.05 to 1.94 and aOR: 1.57; 95% CI 1.13 to 2.15, respectively). Increased parity and younger age (<24 years) were also associated with unplanned pregnancy (aOR: 1.42; 95% CI 1.25 to 1.60 and aOR: 1.83; 95% CI 1.23 to 2.74, respectively).

Conclusions: We observed high levels of unplanned pregnancy among HIV-positive women, particularly among those not on ART, suggesting ongoing missed opportunities for improved family planning and counselling services for HIV-positive women.