BJOG An International Journal of Obstetrics and Gynaecology BJOG An International Journal of Obstetrics and Gynaecology, 2009, 116 (7), pp.943-52. ⟨10.1111/j.1471-0528.2009.02160.x⟩ BJOG: An International Journal of Obstetrics and Gynaecology BJOG: An International Journal of Obstetrics and Gynaecology, 2009, 116 (7), pp.943-52. ⟨10.1111/j.1471-0528.2009.02160.x⟩