Pregnancy Rates and Predictors of Conception, Miscarriage and Abortion in US Women with HIV

Objective: To determine frequency and outcomes of pregnancy in US women with HIV before and after introduction of highly active antiretroviral therapy (HAART).

Design: Prospective cohort study at six US centers.

Methods: HIV seropositive and at-risk seronegative women reported pregnancy outcomes at 6-month intervals during the period 1 October 1994 to 31 March 2002. Outcomes were tabulated and pregnancy rates calculated. Logistic regression defined outcome correlates.

Results: Pregnancy rates were 7.4 and 15.2 per 100 person-years in seropositive and seronegative women, respectively (P < 0.0001). Among seropositives, 119 (36%) pregnancies ended in live birth, six (2%) in stillbirth, 126 (36%) in abortion, 83 (24%) in miscarriage, 16 (5%) in ectopic pregnancy, and two (1%) in other outcomes (P = nonsignificant versus seronegatives). Independent baseline correlates of conception in seropositives included younger age [odds ratio (OR), 1.20; 95% confidence interval (CI), 1.16-1.23], prior abortion (OR, 1.79; 95% CI, 1.25-2.63), lower HIV RNA levels (OR, 1.30; 95% CI, 1.10-1.54 for each log decrease), and being unmarried (OR, 1.59; 95% CI, 1.02-2.44). Baseline antiretroviral use at baseline was linked to lower conception risk (OR, 0.34; 95% CI, 0.49-0.98 for mono- or combination therapy; OR, 0.34; 95% CI, 0.03-4.28 for HAART). Abortion was less likely during the HAART era, (OR, 0.68; 95% CI, 0.35-1.33 during the early HAART era; OR, 0.46; 95% CI, 0.23-0.90 during the later HAART era, compared with before HAART).

Conclusions: Women with HIV were less likely to conceive than at-risk uninfected women, but pregnancy outcomes were similar. Abortion became less common after the introduction of HAART.