BACKGROUND: With the development and widespread use of combination antiretroviral therapy, HIV-infected women live longer, healthier lives. Previous research has shown that, since the adoption of combination antiretroviral therapy in the U.S., rates of morbidity and adverse obstetric outcomes remained higher for HIV-infected pregnant women compared with HIV-uninfected pregnant women. Monitoring trends in the outcomes these women experience is essential, as recommendations for this special population continue to evolve with the progress of HIV treatment and prevention options. OBJECTIVE(S): We conducted an analysis comparing rates of hospitalizations and associated outcomes among HIV-infected and uninfected pregnant women in the United States from 2004-2011. STUDY DESIGN: We used cross-sectional hospital discharge data from the 2004, 2007, and 2011 Nationwide Inpatient Sample, a nationally representative sample of US hospital discharges. Demographic characteristics, morbidity outcomes, and time trends were compared using chi2 tests and multivariate logistic regression. Analyses were weighted to produce national estimates. RESULTS: In 2011, there were 4,751 estimated pregnancy hospitalizations and 3,855 delivery hospitalizations for HIV-infected pregnant women; neither increased since 2004. Compared with those of HIV-uninfected women, pregnancy hospitalizations of HIV-infected women were more likely to be longer, in the South and Northeast, covered by public insurance, and to incur higher charges (all p < 0.005). Hospitalizations among pregnant women who were HIV-infected had higher rates for many adverse outcomes. Compared to 2004, hospitalizations of HIV-infected pregnant women in 2011 had higher odds of gestational diabetes (1.81 [1.16, 2.84]), pre-eclampsia/hypertensive disorders of pregnancy (1.58 [1.12, 2.24]), viral/mycotic/parasitic infections (1.90 [1.69, 2.14]), and bacterial infections (2.54 [1.53, 4.20]). Bacterial infections did not increase among hospitalizations of HIV-uninfected pregnant women. CONCLUSIONS: The numbers of hospitalizations during pregnancy and delivery have not increased for HIV-infected women since 2004, a departure from previously estimated trends. Pregnancy hospitalizations of HIV-infected women remain more medically complex than those of uninfected women. An increasing trend in infections among the delivery hospitalizations of HIV-infected pregnant women warrant further attention.