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Zondervan K, Barlow DH.Zondervan K, et al. Among authors: barlow dh.Baillieres Best Pract Res Clin Obstet Gynaecol. 2000 Jun;14(3):403-14. doi: 10.1053/beog.1999.0083.Baillieres Best Pract Res Clin Obstet Gynaecol. 2000.PMID: 10962634Review.