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Berghella V, Iams JD, Newman RB, Macpherson C, Goldenberg RL, Mueller-Heubach E, Caritis SN, Dombrowski MP; National Institute of Child Health and Human Development Network of Maternal-Fetal Medicine Units.Berghella V, et al.Am J Obstet Gynecol. 2004 Oct;191(4):1253-6. doi: 10.1016/j.ajog.2004.03.012.Am J Obstet Gynecol. 2004.PMID: 15507949