Data collection
The anonymized data on women’s demographic and clinical data, an indication and type of surgical treatment, pregnancy and delivery were obtained by linking three computerized databases: Computerized database of reproductive surgery at the Department of Human Reproduction, National Register of Assisted Reproduction Technology (NRART) and National Perinatal Information System (NPIS). The data included in databases are collected during the hospital stay by attending doctors, nurses, and midwives. The Computerized database of reproductive surgery was described in detail elsewhere (10). The NRART was introduced in 1983 at the Ministry of Health of Republic of Slovenia, and from 1999 the data are also sent to the IVF Monitoring (EIM) Consortium of the European Society of Human Reproduction and Embryology regularly. The data from NPIS, which also serves as a birth registry, are sent to the Slovenian National Institute of Public Health yearly where they go through statistical quality checks, are edited, and form the basis for the official perinatal Statistics of Slovenia. The data from NPIS are also sent to the Vermont Oxford Network and Euro-Peristat.