Studies of rare, but complex clinical conditions require multicenter cooperation. The International Society for Placenta accreta spectrum (IS-PAS) have established a secure web-based database to analyze pregnancies complicated by PAS. By repeated in-person meetings of the IS-PAS, a core dataset was established. Then, a custom-made, secure online database, capable of receiving strictly anonymized patient-related textual and imaging data and allowing statistical queries was designed, tested, amended and implemented. Between 2008 and 2019, 14 IS-PAS centers across Europe and one center in the USA contributed data for all their PAS cases, containing pregnancy data for a total of 442 pregnant women. Data were analyzed by a designated data analysis sub-group of the IS-PAS. Center characteristics are presented. Based on experiences with previous versions, our new online database now allows an all-encompassing data collection. It has shown its usefulness in the current analysis project.
