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Vollebregt KC, Boer K, Van Der Post JA, Wolf H.Vollebregt KC, et al. Among authors: boer k.Acta Obstet Gynecol Scand. 2013 Jan;92(1):53-60. doi: 10.1111/j.1600-0412.2012.01510.x.Acta Obstet Gynecol Scand. 2013.PMID: 22881432Free article.