Nearly half of pregnancies in the United States are unintended1 and frequently result in adverse outcomes for women and families. Reducing the high rate of unintended pregnancy is a national priority of the US Department of Health and Human Services, reflected in the Healthy People 2020 goal of decreasing the proportion of unintended pregnancies by 10%.2 Of the 3 most commonly used contraceptive methods in the United States—sterilization, oral contraceptives, and condoms3—only sterilization is considered a highly effective method by the Centers for Disease Control and Prevention and by the World Health Organization.4