Trends of and factors associated with live-birth and abortion rates among HIV-positive and HIV-negative women

BackgroundLittle is known about fertility choices and pregnancy outcome rates among HIV-infected women in the current combination antiretroviral treatment era.ObjectiveWe sought to describe trends and factors associated with live-birth and abortion rates among HIV-positive and high-risk HIV-negative women enrolled in the Women's Interagency HIV Study in the United States.Study DesignWe analyzed longitudinal data collected from Oct. 1, 1994, through Sept. 30, 2012, through the Women's Interagency HIV Study. Age-adjusted rates per 100 person-years live births and induced abortions were calculated by HIV serostatus over 4 time periods. Poisson mixed effects models containing variables associated with live births and abortions in bivariable analyses (P < .05) generated adjusted incidence rate ratios and 95% confidence intervals.ResultsThere were 1356 pregnancies among 2414 women. Among HIV-positive women, age-adjusted rates of live birth increased from 1994 through 1997 to 2006 through 2012 (2.85-7.27/100 person-years, P trend < .0001). Age-adjusted rates of abortion in HIV-positive women remained stable over these time periods (4.03-4.29/100 person-years, P trend = .09). Significantly lower live-birth rates occurred among HIV-positive compared to HIV-negative women in 1994 through 1997 and 1997 through 2001, however rates were similar during 2002 through 2005 and 2006 through 2012. Higher CD4+ T cells/mm3 (≥350 adjusted incidence rate ratio, 1.39 [95% CI 1.03-1.89] vs <350) were significantly associated with increased live-birth rates, while combination antiretroviral treatment use (adjusted incidence rate ratio, 1.35 [95% CI 0.99-1.83]) was marginally associated with increased live-birth rates. Younger age, having a prior abortion, condom use, and increased parity were associated with increased abortion rates among both HIV-positive and HIV-negative women. CD4+ T-cell count, combination antiretroviral treatment use, and viral load were not associated with abortion rates.ConclusionUnlike earlier periods (pre-2001) when live-birth rates were lower among HIV-positive women, rates are now similar to HIV-negative women, potentially due to improved health status and combination antiretroviral treatment. Abortion rates remain unchanged, illuminating a need to improve contraceptive services.