Objective: To evaluate whether early luteal E2 or human chorionic gonadotropin (HCG) supplementation in patients undergoing IVF cycle with profound E2 decline will affect reproductive outcome.Design: Prospective randomized study.Materials/Methods: Between January 1999 and December 2001, a total of 331 patients undergoing IVF cycles with severe early luteal E2 decline were enrolled. Serum E2 levels were measured on the day of HCG administration (E0)and day of embryo transfer(Et). Only patients with severe decline in E2 levels (E0/Et >50%) were included. They were randomized into 2 groups: Group 1 included 171 patients who received E2(n = 88) or HCG (n = 83) rescue on the day of embryo transfer. Group 2 included 160 patients who received no rescue. Downregulation was achieved with leuprolide acetate in the depot form and ovarian stimulation with recombinant FSH, human menopausal gonadotropin or combined.Results: Mean female age was 29.2 in the treated group 1 compared to 29.1 in the untreated group 2. The difference was not statistically significant (p >0.05). There was no statistically significant difference in stimulation and downregulation protocols, ampules of gonadotropin used, days of stimulation, mean number of eggs retrieved, mean number of embryos transferred and type of embryo transfer between the 2 groups. Higher implantation, ongoing and multiple pregnancy rates were achieved in group 1 (14.5%, 44.4% and 28.4%) compared to group 2 (10%,31.9% and 13.6%). The difference was statistically significant (p <0.02). There was a trend towards lower miscarriage rate in group 1 (6.2%) compared to group 2 (13.6%). The difference was not statistically significant (p >0.05). Results are shown in table I. Table IOutcome of IVF in patients with early luteal E2 decline in the treated and untreated groups.Group 1 (treated) n = 171Group 2 (untreated) n = 160Fertilization rate77.877.0Implantation rate∗The difference is statistically significant (p < 0.05).14.510.0Clinical pregnancy rate/embryo transfer47.436.9Ongoing pregnancy rate/embryo transfer∗The difference is statistically significant (p < 0.05).44.431.9Miscarriage rate6.213.6Multiple pregnancy rate∗The difference is statistically significant (p < 0.05).28.413.6∗ The difference is statistically significant (p < 0.05). Open table in a new tab Conclusions: Early supplementation with estradiol or HCG in patients with profound E2 decline may improve the reproductive outcome. Measuring serum E2 levels in the early luteal phase seems to be an important measure in the management of IVF patients.Supported by: IVF Michigan. Objective: To evaluate whether early luteal E2 or human chorionic gonadotropin (HCG) supplementation in patients undergoing IVF cycle with profound E2 decline will affect reproductive outcome. Design: Prospective randomized study. Materials/Methods: Between January 1999 and December 2001, a total of 331 patients undergoing IVF cycles with severe early luteal E2 decline were enrolled. Serum E2 levels were measured on the day of HCG administration (E0)and day of embryo transfer(Et). Only patients with severe decline in E2 levels (E0/Et >50%) were included. They were randomized into 2 groups: Group 1 included 171 patients who received E2(n = 88) or HCG (n = 83) rescue on the day of embryo transfer. Group 2 included 160 patients who received no rescue. Downregulation was achieved with leuprolide acetate in the depot form and ovarian stimulation with recombinant FSH, human menopausal gonadotropin or combined. Results: Mean female age was 29.2 in the treated group 1 compared to 29.1 in the untreated group 2. The difference was not statistically significant (p >0.05). There was no statistically significant difference in stimulation and downregulation protocols, ampules of gonadotropin used, days of stimulation, mean number of eggs retrieved, mean number of embryos transferred and type of embryo transfer between the 2 groups. Higher implantation, ongoing and multiple pregnancy rates were achieved in group 1 (14.5%, 44.4% and 28.4%) compared to group 2 (10%,31.9% and 13.6%). The difference was statistically significant (p <0.02). There was a trend towards lower miscarriage rate in group 1 (6.2%) compared to group 2 (13.6%). The difference was not statistically significant (p >0.05). Results are shown in table I. Conclusions: Early supplementation with estradiol or HCG in patients with profound E2 decline may improve the reproductive outcome. Measuring serum E2 levels in the early luteal phase seems to be an important measure in the management of IVF patients. Supported by: IVF Michigan.