[1] Univ Calabar, Teaching Hosp, Dept Obstet & Gynaecol, Calabar, Nigeria
[2] Univ Port Harcourt, Teaching Hosp, Dept Obstet & Gynaecol, Port Harcourt, Nigeria
[3] Univ Uyo, Teaching Hosp, Dept Obstet & Gynaecol, Uyo, Nigeria
[4] Delta State Univ, Teaching Hosp, Dept Obstet & Gynaecol, Abraka, Nigeria
[5] Irrua Specialist Teaching Hosp, Dept Obstet & Gynaecol, Irrua, Edo State, Nigeria
[6] Univ Benin, Teaching Hosp, Dept Obstet & Gynaecol, Benin, Nigeria
[7] Faith Mediplex Hosp, Dept Obstet & Gynaecol, Benin, Edo State, Nigeria
[8] St Philomena Hosp, Dept Obstet & Gynaecol, Benin, Edo State, Nigeria
[9] Niger Delta Univ, Wilberforce Highland, Nigeria
[10] World Hlth Org, Dept Ageing & Life Course, Nigeria Country Off, Abuja, Nigeria
[11] Niger Delta Univ, Teaching Hosp, Dept Obstet & Gynaecol, Okolobiri, Bayelsa State, Nigeria
[12] World Hlth Org, Dept Sexual & Reprod Hlth & Res, World Bank Special Programme Res Dev & Res Trainin, UNDP,UNFPA,UNICEF,WHO, Geneva, Switzerland
[13] Aminu Kano Teaching Hosp, Dept Obstet & Gynaecol, Kano, Nigeria