Advancing age is associated with increased AUC (area under the curve) for E2 (estradiol) production per mature follicle and decreased AUC per FSH stimulation irrespective to the protocol of ovarian stimulation

Abstract

Objective: To study the effect of age on the pattern of estrogen production per mature ovarian follicle and in response to FSH stimulation during different ovarian stimulation protocols Design: Retrospective. Materials and Methods: Patients undergoing ovarian stimulation in conjunction with intrauterine insemination or for IVF-ET (in vitro fertilization and embryo transfer) have been included from two tertiary referral academic infertility centers in the period from January 2000 and July 2002. Patients were divided into two groups, first group included patients who underwent COH (controlled ovarian hyperstimulation) for IVF-ET (226 patients had 254 cycles). Both standard and microdose flare protocol were applied for COH. The second group included 357 patients who received different ovarian stimulation protocols in conjunction with IUI (intrauterine insemination) in 493 cycles. Clomiphene citrate was used alone in 176 cycles and in conjunction with FSH in 28 cycles, FSH injection alone in 87 cycles, letrozole (an aromatase inhibitor) was used alone in 84 cycles and in conjunction with FSH in 118 cycles). The AUC for E2 production was calculated from available daily E2 levels along the follicular phase starting on the first day of ovarian stimulation until the day of hCG administration (or endogenous LH surge in IUI cycles). AUC for E2 production per FSH unit administered (AUC/FSH) as well as the AUC for E2 produced per mature follicle (AUC/follicle) were calculated. Patients were sub-grouped according to the age in ascending matter. Each patient group was analyzed separately and after subdividing them according to the protocol of ovarian stimulation. Results: Group 1 (IVF) patients had a positive correlation between AUC/follicle and advancing age (P<0.05) and a negative correlation between AUC/FSH and advancing age (P<0.05). This was true when all patients were analyzed together and after subgrouping according to the stimulation protocol (long standard and microdsoe flare up protocol). The same findings were found in the second patient group when all patients were analyzed together and when subdivided into different ovarian stimulation protocol. Pregnancy rates negatively correlated well with advancing age as expected and was also negatively correlating with increasing AUC/follicle and decreasing AUC/FSH. The effect of age on AUC/follicle, AUC/FSH and Pregnancy Rate in IVF-ET cycles Tabled 1 View Large Image Figure ViewerDownload (PPT) Conclusions: High AUC/follicle and low AUC/FSH seem to be features of advancing age irrespective of type of ovarian stimulation. Both parameters also might serve as predictors for poor treatment outcome.