Unilateral Oophorectomy Increases Antral Follicle Responsiveness to Exogenous Fsh, As Assessed by Follicular Output Rate (fort), in Normo-Cycling Women Undergoing Controlled Ovarian Hyperstimulation

ObjectiveAlthough the possible compensating mechanisms at play in the maintenance of ovarian lifespan in women unilaterally oophorectomized remain unclear, it is conceivable that changes in the sensitivity of growing follicles to FSH may occur, to ensure cyclic recruitment and ovulation. To investigate this issue, we hypothesized that responsiveness of antral follicles to exogenous FSH would be enhanced in unilaterally oophorectomized patients as compared to women having two ovaries. We elected to assess follicle responsiveness to FSH by calculating the FORT, an innovative tool which results are independent of the size of pretreatment cohort of antral follicles.DesignProspective study.Materials and MethodsWe studied 64 IVF-ET candidates, 26-40 years of age, having a single remaining ovary, as a result unilateral oophorectomy (One Ovary group; n = 32) or two ovaries (Control group; n = 32). Women in both groups were matched according to age, day-3 serum AMH levels, and controlled ovarian hyperstimulation protocol. Antral follicle (3-9 mm) count (AFC) and preovulatory follicle (16-22 mm) count (PFC) were measured, respectively, just before FSH treatment and on the day of hCG administration. The FORT was calculated by PFCx100/AFC.ResultsMean ages and day-3 AMH levels were similar in the One Ovary and Control groups (33.5 ± 0.6 vs. 33.5 ± 0.6 years and 2.39 ± 0.3 vs. 2.0 ± 0.2 ng/mL, respectively). While mean AFC at baseline were comparable in both groups (8.9 ± 0.4 vs. 9.1 ± 0.4 follicles), after a similar total amount of exogenous gonadotropins (2963 ± 146 vs. 3310 ± 143 IU, NS), FORT was significantly increased in women of the One Ovary group (55.8 ± 2.8% vs. 44.3 ± 2.0%, P<0.001).ConclusionThat the responsiveness of antral follicles to exogenous FSH, as far as it is measurable by the FORT, was increased in women having one single ovary, supports the hypothesis that increased FSH sensitivity ranks among the possible compensating mechanisms at stake in the maintenance of successful folliculogenesis after unilateral oophorectomy. ObjectiveAlthough the possible compensating mechanisms at play in the maintenance of ovarian lifespan in women unilaterally oophorectomized remain unclear, it is conceivable that changes in the sensitivity of growing follicles to FSH may occur, to ensure cyclic recruitment and ovulation. To investigate this issue, we hypothesized that responsiveness of antral follicles to exogenous FSH would be enhanced in unilaterally oophorectomized patients as compared to women having two ovaries. We elected to assess follicle responsiveness to FSH by calculating the FORT, an innovative tool which results are independent of the size of pretreatment cohort of antral follicles. Although the possible compensating mechanisms at play in the maintenance of ovarian lifespan in women unilaterally oophorectomized remain unclear, it is conceivable that changes in the sensitivity of growing follicles to FSH may occur, to ensure cyclic recruitment and ovulation. To investigate this issue, we hypothesized that responsiveness of antral follicles to exogenous FSH would be enhanced in unilaterally oophorectomized patients as compared to women having two ovaries. We elected to assess follicle responsiveness to FSH by calculating the FORT, an innovative tool which results are independent of the size of pretreatment cohort of antral follicles. DesignProspective study. Prospective study. Materials and MethodsWe studied 64 IVF-ET candidates, 26-40 years of age, having a single remaining ovary, as a result unilateral oophorectomy (One Ovary group; n = 32) or two ovaries (Control group; n = 32). Women in both groups were matched according to age, day-3 serum AMH levels, and controlled ovarian hyperstimulation protocol. Antral follicle (3-9 mm) count (AFC) and preovulatory follicle (16-22 mm) count (PFC) were measured, respectively, just before FSH treatment and on the day of hCG administration. The FORT was calculated by PFCx100/AFC. We studied 64 IVF-ET candidates, 26-40 years of age, having a single remaining ovary, as a result unilateral oophorectomy (One Ovary group; n = 32) or two ovaries (Control group; n = 32). Women in both groups were matched according to age, day-3 serum AMH levels, and controlled ovarian hyperstimulation protocol. Antral follicle (3-9 mm) count (AFC) and preovulatory follicle (16-22 mm) count (PFC) were measured, respectively, just before FSH treatment and on the day of hCG administration. The FORT was calculated by PFCx100/AFC. ResultsMean ages and day-3 AMH levels were similar in the One Ovary and Control groups (33.5 ± 0.6 vs. 33.5 ± 0.6 years and 2.39 ± 0.3 vs. 2.0 ± 0.2 ng/mL, respectively). While mean AFC at baseline were comparable in both groups (8.9 ± 0.4 vs. 9.1 ± 0.4 follicles), after a similar total amount of exogenous gonadotropins (2963 ± 146 vs. 3310 ± 143 IU, NS), FORT was significantly increased in women of the One Ovary group (55.8 ± 2.8% vs. 44.3 ± 2.0%, P<0.001). Mean ages and day-3 AMH levels were similar in the One Ovary and Control groups (33.5 ± 0.6 vs. 33.5 ± 0.6 years and 2.39 ± 0.3 vs. 2.0 ± 0.2 ng/mL, respectively). While mean AFC at baseline were comparable in both groups (8.9 ± 0.4 vs. 9.1 ± 0.4 follicles), after a similar total amount of exogenous gonadotropins (2963 ± 146 vs. 3310 ± 143 IU, NS), FORT was significantly increased in women of the One Ovary group (55.8 ± 2.8% vs. 44.3 ± 2.0%, P<0.001). ConclusionThat the responsiveness of antral follicles to exogenous FSH, as far as it is measurable by the FORT, was increased in women having one single ovary, supports the hypothesis that increased FSH sensitivity ranks among the possible compensating mechanisms at stake in the maintenance of successful folliculogenesis after unilateral oophorectomy. That the responsiveness of antral follicles to exogenous FSH, as far as it is measurable by the FORT, was increased in women having one single ovary, supports the hypothesis that increased FSH sensitivity ranks among the possible compensating mechanisms at stake in the maintenance of successful folliculogenesis after unilateral oophorectomy.