Guttmacher Alan E, Spong Catherine Y
Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD.
Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD.
Am J Obstet Gynecol. 2015 Oct;213(4 Suppl):S3-5. doi: 10.1016/j.ajog.2015.08.037.