FDA initiated this analysis to better understand utilization of hydroxyprogesterone caproate (HPC) injection, including Makena® and its generics, among pregnant women in the United States. We identified a total of 3,445,739 live-birth pregnancies (among 2.9 million women) between 2008 and 2018 in the Sentinel Distributed Database (SDD). Of these pregnancies, 6.5 per 1,000 pregnancies used injectable HPC, showing modest use of injectable HPC during the second and/or third trimesters among all live-birth pregnancies in the SDD. The majority (73%) of pregnancies with injectable HPC use had at least one of three obstetrical indications of interest recorded before or during the pregnancy. Sentinel analysis results were presented at an FDA Advisory Committee Meeting for consideration in assessing the potential public health impact of withdrawing Makena’s accelerated drug approval. Following the FDA Advisory Committee Meeting, the FDA’s Center for Drug Evaluation and Research (CDER) recommended withdrawing Makena’s accelerated approval.