Factors influencing success rate of IVF/ET:analysis of 770 treatment cycles

Objective:To evaluate the factors influencing success rate of in vitro fertilization/embryo transfer(IVF/ET).Methods:A retrospective study of 770 consecutive cycles undergone IVF/ET or in-tracytoplasmic sperm injection(ICSI)from March 1999 to June 2001.Estradiol and pro-gesterone concentrations on the day of hCG administration were measured.Factors effecting embryo transfer on the effects of clinical pregnancy rate were evaluated.Results:The overall clinical pregnancy rate in 770 cycles was 40.8%.Take home baby rate was 31%.No significantly differences rate were observed between groups with different estradiol levels.If the progesterone concentration on the day of hCG ad-ministration was>6.36 nmol/L,the implantation and clinical pregnancy rate was lower(P<0.003).The lowest clinical pregnancy rate was observed when the duration of in-fertility was≥10 years.The average number of embryos transferred was 2.23±0.83.Conclusion:This study demonstrated that the most important factor on clinical pregnancy rate was low progesterone concentration on the day of hCG administration.The other two important variables influencing success rate of IVF/ET were the duration of infertility,the number of high-grade embryos transferred.