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Reddy UM, Filly RA, Copel JA; Pregnancy and Perinatology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Department of Health and Human Services, NIH.Reddy UM, et al.Obstet Gynecol. 2008 Jul;112(1):145-57. doi: 10.1097/01.AOG.0000318871.95090.d9.Obstet Gynecol. 2008.PMID: 18591320Free PMC article.