ROLE OF ATTEMPT RANK IN IN-VITRO FERTILIZATION

The French national register on in vitro fertilization (IVF) Fivnat, w hich has collected most of the oocyte pick-ups realised in France sinc e 1986 has allowed us to build a cohort of 35714 couples, of which the first recovery took place between 1990 and 1994 and followed up to a pregnancy or to the 31st of december, 1996.. The per recovery clinical pregnancy rate decreased from 20.2% on the first attempt to 17.4% on the second, and to less than 13% after the sixth. This evolution exist ed whatever the women's age class or the infertility diagnosis. The wo men's age remained the most important factor, since the cumulative pre gnancy rate decreased from 60% for women aged less than 35 years to 17 % for those aged more than 41 years. Among the indications, male infer tility using spouse's semen had the poorest prognosis, especially for women aged more than 41 years (9.6%) whereas male infertility using do nor's semen among women aged less than 35 years was associated to the best results (68%). It must be noticed than a high percentage of unpre gnant women did not come again for a further recovery (40% to 50%). Th en, the crude cumulative birth rate (24,4%) was far below the theoreti cal cumulative one(54.2%).