VARIATIONS IN IVF SUCCESS FACTORS ACCORDI NG TO THE RANK OF ATTEMPTS

Data from all IVF cycles of 8 362 patients that were initiated their f irst attempt between 1986 and 1987 were analysed until a clinical preg nancy was achieved or they withdrew from the program. The general char acteristics, success rate and success factors are the same that indica ted in FIVNAT analysis. The transfer rate and the number of transfered embryos increase according to the rank of attempt. By contrast, the p regnancy rate declines with successive cycles. After each cycle the pe rcent of cancelled attempt is high (40 %). This cancelled rate is not associated with infertility diagnoses. It increases with women's age a nd especially with the failure of fecondation. All the same, the cance lled rate is frequent among all patients and asks us about risk factor s and prevention.