Resultaten van in-vitrofertilisatie in Nederland, 1996-2000

OBJECTIVE: To describe the annual results in all 13 Dutch in vitro fertilisation (IVF) centres in the period 1996-2000, and to look for possible differences between individual centres and years. DESIGN: Retrospective data collection, description and analysis. METHOD: The results collected on the website of the Dutch Society of Obstetrics and Gynaecology (Dutch acronym: NVOG; www.nvog.nl) in the period 1996-2000 were integrated and described, with special attention to possible differences between centres and years. RESULTS: In 1996-2000 (5 years), 63,414 IVF or ICSI treatment cycles were started in the Netherlands, and 5,884 transfers of cryopreserved embryos were performed. The number of treatment cycles increased over the years, particularly the number of ICSI cycles. The total number of ongoing pregnancies was 12,991 (20.5% per started cycle; 22.5% for ICSI and 18.3% for IVF). Particularly during the first 3 years, there was an increase in these percentages (IVF: from 16.4% (1996) to 19.2% (1998); ICSI: from 18.3% (1996) to 23.9% (1998)). There were differences between the centres in both the percentage of ongoing pregnancies per started IVF/ICSI cycle (range 13.7-25.1%) and the percentage ICSI (14-61%) and cryo-transfers per total number of treatment cycles (0-26%). It was estimated that, during this 5-year period, 1 out of every 61 Dutch neonates resulted from IVF or ICSI. CONCLUSION: The pregnancy-rates after IVF and ICSI increased during the study period, and were comparable with the rates in other European countries. Some important data are still missing from the inventory, for example regarding the number of embryos per transfer, multiple pregnancies, live births, congenital malformations and complication