Lopinavir/ritonavir in pregnancy.

Objective: The Antiretroviral Pregnancy Registry was established in 1989 to collect data on birth defects after pregnancy exposures to antiretroviral therapy. Using Registry data, this study estimates the birth defect risk after pregnancy exposures to lopinavir/ritonavir. Methods: The analysis population includes all prospective lopinavir/ritonavir-exposed pregnancies enrolled in the Registry from September 2000 through July 2007. Birth defect prevalence after pregnancy exposure is compared with rates from a population-based surveillance system, and first-trimester exposures are compared with combined second/third-trimester exposures. Results: Among 955 live births prenatally exposed to lopinavir/ritonavir, 23 cases with birth defects were reported [2.4%, 95% confidence interval (CI) = 1.5 to 3.6). Among 267 live births with first-trimester exposures, 5 had birth defects (1.9%, 95% CI = 0.6 to 4.3). These rates are similar to the population-based comparator rate of 2.67% and the rate in infants with second/third-trimester exposures (2.6%, 95% CI = 1.6 to 4.1). No pattern of birth defects suggestive of a common etiology was seen. Conclusions: The prevalence of birth defects among infants prenatally exposed to lopinavir/ritonavir is not significantly different from internal or external comparison groups. These data provide reassuring information to patients and clinicians about the safety of lopinavir/ritonavir in the treatment of HIV-positive pregnant women.