Impact of Gonadotrophin Dose on Ovarian Stimulation for IVF and Embryo Ploidy: A Cohort Study

Author(s): Alessandro Schuffner, Gabriela Schuffner, Camila Dutra De Souza Francisquini, Matheus Campos Carneiro, Isadora Ferreira Kozlowski, Samara Artuso Giacomin, Vinicius Bonato Da Rosa

The relationship between gonadotropin dosage and embryo ploidy status in in vitro fertilization (IVF) remains controversial, with previous studies yielding conflicting results. While some evidence suggests that higher gonadotropin doses may increase aneuploidy rates due to meiotic disruption, other investigations have not confirmed this association. In this retrospective cohort study, we evaluated the impact of total gonadotropin dose administered during controlled ovarian stimulation on the number of euploid embryos obtained following preimplantation genetic testing for aneuploidies (PGT-A).A total of 245 patients were allocated into two groups according to gonadotropin dosage (≤3000 IU, n=150; >3000 IU, n=95). Patients in the lower-dose group exhibited a shorter stimulation period and a significantly higher number of follicles, oocytes, metaphase II oocytes, zygotes, blastocysts, and euploid blastocysts. Subgroup analysis according to stimulation protocol demonstrated superior outcomes in younger patients receiving recombinant FSH (rFSH) alone, including higher follicular counts, oocyte yield, and euploid embryo numbers. Furthermore, infertility diagnosis influenced the outcomes, with male factor and unexplained infertility groups achieving better embryological parameters compared to those with female factor or combined female and male factors. Notably, the unexplained infertility group yielded the highest number of euploid blastocysts, whereas the combined female plus male factor group demonstrated the lowest euploidy rates. A positive correlation was observed between embryo production and euploidy, while maternal age and higher gonadotropin doses correlated negatively with euploid outcomes. These findings suggest that lower gonadotropin doses, particularly within rFSH-only protocols, may enhance embryo chromosomal integrity and improve clinical outcomes in IVF.