1. Department of Obstetrics and Gynecology Stellenbosch University and Tygerberg Academic Hospital Cape Town South Africa
2. Department of Obstetrics and Gynecology Amsterdam UMC Vrije Universiteit Amsterdam Amsterdam The Netherlands
3. Department of Obstetrics and Gynecology Leiden University Medical Center Leiden The Netherlands
4. Athena Institute Vrije Universiteit Amsterdam Amsterdam The Netherlands
5. Department of Epidemiology and Data Science Amsterdam Public Health Amsterdam UMC Vrije Universiteit Amsterdam Amsterdam The Netherlands