[Evaluation of FIVNAT 1992].

FIVNAT registry collected information on 21,960 individual assisted reproductive technology (ART) cycles in 1992. The present analysis concerns 15,557 cycles arrived on time to be incorporated, 97.9% being in vitro fertilization (IVF) cycles. The transfer rate was 80.9% and the clinical pregnancy rate was 19.2% per oocyte recovery cycle and 23.7% per transfer. The mean oocyte number slightly increased compared to 1991 (8.5 +/- 5.6 vs 8.2 +/- 5.6, p < 0.001) whereas the mean number of embryos obtained was not modified and the mean number of transferred oocytes slightly decreased. The mean fertilization rate slightly increased (53.0% +/- 30.2% vs 48.3% +/- 32.7%, p < 0.001). Infertility of tubal origin represented 59.1% of infertilities, and cycles realised with donor semen were associated to the highest pregnancy rate. GnRH analogues were widely used (87.5%), but those using a short blocking period tended to decrease, replaced by protocols without GnRH analogues. Stimulation regimen using a long blockage phase were associated to a higher pregnancy rate than the others (19.8% per recovery). The proportion of transfers involving 4 or more embryos decreased in 1991 to 22.9%. The analysis of 7,960 pregnancy forms resulting of recoveries realised from 1987 to 1991 showed a preterm birth rate of 9.2% for singleton, but a still high rate for twins and multiple pregnancies. For singleton pregnancies, in utero mortality concerned 6.9/1000 of the children, and the neonatal mortality rate (< 7 days) was 6.7/1000. The overall malformation rate was 2.8%.