摘要：To study the impact of the introduction of reimbursement of in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) laboratory costs in Belgium which is linked to an embryo transfer strategy leading to prevention of multiple pregnancies. The impact on the incidence of multiple and twin pregnancy rate as well as on ongoing pregnancy rate in our centre is calculated. Study design: Observational cohort study of all patients in the first year (July 1, 2003- June 30, 2004)- since the implementation of the law and comparison of ongoing pregnancy rate and multiple pregnancy rate of our centre with Belgian data. Results: Our results of one year of IVF/ICSI since reimbursement of laboratory costs show a total conception rate of 42.2% with 29.7% ongoing pregnancies beyond 25 weeks amenorrhea. The multiple pregnancy rate was 8.5% including five monozygotic twin pregnancies. These data show an important decline of multiple pregnancy ratewhen compared to Belgian data (2002) with 24.4% multiple pregnancy rate in the year prior to reimbursement. Conclusion: The introduction of reimbursement of IVF/ICSI laboratory costs coupled to a restriction in the number of embryos for transfer has reached the goal of halving the multiple pregnancy rate since its introduction while maintaining an optimal ongoing pregnancy rate.