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Bristow SE, Hilton P.Bristow SE, et al. Among authors: hilton p.Baillieres Best Pract Res Clin Obstet Gynaecol. 2000 Apr;14(2):227-49. doi: 10.1053/beog.1999.0073.Baillieres Best Pract Res Clin Obstet Gynaecol. 2000.PMID: 10897321Review.