Lack of association between polycystic ovary syndrome and embryonic aneuploidy

Objective

To determine whether women with polycystic ovary syndrome (PCOS) are at increased risk for embryonic aneuploidy.

Design

Retrospective cohort study.

Setting

Academic teaching department, privately owned preimplantation genetics laboratory, and academically affiliated, private infertility center.

Patient(s)

The study included 174 women, ages 27–45 years, who underwent a single cycle of controlled ovarian hyperstimulation with gonadotropins for in vitro fertilization. Amongst those, 74 were proven patients with PCOS, and 100 were control women with proven absence of PCOS.

Intervention(s)

Preimplantation genetic diagnosis for chromosomes X, Y, 13, 15, 16, 17, 18, 21, and 22.

Main Outcome Measure(s)

Embryonic morphology, in vitro fertilization cycle outcome parameters, and euploidy and aneuploidy rates.

Result(s)

Women with PCOS demonstrated similar overall percentages of euploid embryos (49.1% ± 28.1) when compared with control women (51.8% ± 30.1). However, a statistically significantly higher oocyte yield in patients with PCOS (22.8 ± 9.8 vs. 16.5 ± 7.6) resulted in statistically significantly higher absolute numbers of euploid embryos (3.3 ± 2.1 vs. 2.4 ± 2.0). When stratified for age (<38 y and ≥38 y) and egg numbers (10–20 and >20), euploidy rates still did not vary between study and control patients. High-responder patients with PCOS showed, however, statistically significantly reduced clinical- (42.9% vs. 69.0%) and ongoing-pregnancy rates (40.5% vs. 65.5%) compared with high-responder control women.

Conclusion(s)

Women with PCOS are not at increased risk for embryonic aneuploidy in the course of in vitro fertilization treatment. Indeed, because of their larger oocyte numbers, they produce more euploid embryos but have lower pregnancy rates after high oocyte yields. This lower pregnancy rate is, thus, not genetically caused and requires further investigation.

Key Words: Aneuploidy, in vitro fertilization, oocyte numbers, ovarian response, polycystic ovary syndrome, preimplantation genetic diagnosis