OBJECTIVE: The objective of the study was to determine whether protease inhibitors increase glucose intolerance and insulin resistance in pregnancy. STUDY DESIGN: In this multicenter, prospective, observational study, 149 human immunodeficiency virus-1-infected pregnant women had fasting insulin, glucose, and C-peptide measured followed by a 1 hour, 50 g glucose test. Glucose intolerance was defined as a 1 hour glucose greater than 130 mg/dL. Glucose intolerance, homeostasis model assessment of insulin resistance and pancreatic beta-cell function, and pregnancy outcomes were compared between those taking protease inhibitors and those not. RESULTS: Fifty-seven of 149 subjects (38%) had glucose intolerance. Body mass index, Hispanic ethnicity, and maternal age, but not protease inhibitors, were associated with glucose intolerance. There were no differences in insulin resistance, beta-cell function, or pregnancy outcome associated with protease inhibitor use. CONCLUSIONS: Protease inhibitors do not increase risk of glucose intolerance or insulin resistance among pregnant women.