Unexpected hypo-responders in in vitro fertilization: The impact of higher gonadotropin doses on oocyte yield.

Abstract

Objective: This study assessed the impact of increased initial gonadotropin doses on ovarian stimulation (OS) outcomes in unexpected hypo-responders [Patient-Oriented Strategies Encompassing Individualized Oocyte Number (POSEIDON) 1-2 group] with suboptimal mature oocyte yield, despite normal ovarian reserve markers, during their first OS cycle.

Materials and methods: Conducted at a referral infertility clinic, this observational study included women who retrieved fewer than nine oocytes during their first OS cycle despite gonadotropin doses of 150-225 international unit (IU)/day starting from cycle day two. Women who underwent a second OS cycle following unsuccessful conception were included. Gonadotropin doses were increased to 225 or 300 IU recombinant follicle-stimulating hormone (FSH) (recFSH) based on body mass index. Each patient served as her own control, with first and second OS cycles compared in terms of oocyte yield, follicular output ratio (FORT), and follicle-to-oocyte index (FOI).

Results: Among 289 unexpected hypo-responders (12% prevalence), the mean age was 34.2 years, and the mean anti-müllerian hormone level was 3.4 ng/mL. The stimulation duration was similar between cycles (11.2 days). The second OS cycle showed significant improvements in total oocytes, metaphase II oocytes, FORT, FOI, cleavage-stage embryos, and blastocysts (p<0.05).

Conclusion: Increasing gonadotropin doses in subsequent cycles improves oocyte yield and embryological outcomes in unexpected hypo-responders (POSEIDON 1-2) with normal ovarian reserve markers.