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Khalil A, Suff N, Thilaganathan B, Hurrell A, Cooper D, Carvalho JS.Khalil A, et al.Ultrasound Obstet Gynecol. 2014 Jan;43(1):14-24. doi: 10.1002/uog.12526. Epub 2013 Dec 10.Ultrasound Obstet Gynecol. 2014.PMID: 23737029Free article.Review.