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McSorley MA, Alberg AJ, Allen DS, Allen NE, Brinton LA, Dorgan JF, Pollak M, Tao Y, Helzlsouer KJ.McSorley MA, et al.Obstet Gynecol. 2007 Apr;109(4):933-41. doi: 10.1097/01.AOG.0000257126.68803.03.Obstet Gynecol. 2007.PMID: 17400857