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Girsen AI, Mayo JA, Carmichael SL, Phibbs CS, Shachar BZ, Stevenson DK, Lyell DJ, Shaw GM, Gould JB; March of Dimes Prematurity Research Center at Stanford University School of Medicine.Girsen AI, et al.BJOG. 2016 Nov;123(12):2001-2007. doi: 10.1111/1471-0528.14027. Epub 2016 May 13.BJOG. 2016.PMID: 27172996Free PMC article.