[1] Leiden Univ, Obstet, Med Ctr, Leiden, Netherlands
[2] Onze Lieve Vrouw Hosp, Gynaecol & Obstet, Amsterdam, Netherlands
[3] Amsterdam UMC, Locat Meibergdreef, Gyneacol & Obstet, Amsterdam, Netherlands
[4] Amsterdam UMC, Locat Meibergdreef, Gyneacol & Obstet, Locat Boelelaan, Amsterdam, Netherlands
[5] HagaZiekenhuis, Gyneacol & Obstet, The Hague, Netherlands
[6] St Lucas Andreas Ziekenhuis, Gyneacol & Obstet, Amsterdam, Netherlands
[7] Zaans Med Ctr, Gyneacol & Obstet, Amsterdam, Netherlands
[8] UMC Utrecht, Wilhelmina Children Hosp, Birth Ctr, Utrecht, Netherlands
[9] Leiden Univ, Med Ctr, Anaesthesiol, Leiden, Netherlands
[10] Univ Med Ctr Groningen, Anaesthesiol, Groningen, Netherlands
[11] Univ Adelaide, Sch Paediat & Reprod Hlth, Robinson Inst, Adelaide, SA, Australia
[12] Leiden Univ, Med Ctr, Dept Med Decis Making, Leiden, Netherlands