Influence of metabolic syndrome on female fertility and in vitro fertilization outcomes in PCOS women

Abstract

Objective: With a high incidence of insulin resistance, central obesity and dyslipidemia, women with polycystic ovary syndrome are susceptible to metabolic syndrome (MetS). Our objective was to explore whether metabolic syndrome had an effect on overall female fertility and in vitro fertilization outcomes in infertile women with polycystic ovary syndrome.

Study design: This was a secondary analysis of a multicenter randomized trial in 1508 women with polycystic ovary syndrome, which was originally designed to compare the live birth rate after fresh-embryo transfer vs frozen embryo transfer (Frefro-PCOS). At baseline, metabolic parameters, including body mass index, waist and hip circumference, blood pressure, lipid profile, fasting, and 2 hour glucose and insulin levels after a 75 g oral glucose tolerance test were measured. All subjects were divided into a metabolic syndrome group (metabolic syndrome) and absence of metabolic syndrome group (nonmetabolic syndrome) according to diagnostic criteria. Descriptive statistics and logistic regression models tested the association between metabolic syndrome and overall fertility and in vitro fertilization cycle stimulation characteristics and clinical outcomes.

Results: Metabolic syndrome was identified in 410 of 1508 infertile women with polycystic ovary syndrome (27.2%). Patients with metabolic syndrome had longer infertility duration (4.0 ± 2.2 vs 3.7 ± 2.2, P = .004) compared with those without metabolic syndrome. During ovarian stimulation, those with metabolic syndrome required significantly higher and longer doses of gonadotropin and had lower peak estradiol level, fewer retrieved oocytes, available embryos, a lower oocyte utilization rate, and ovarian hyperstimulation syndrome than those with nonmetabolic syndrome. The cumulative live birth rate did not show a significant between-group difference (57.8% vs 62.2%, P = .119). Multivariate logistic regression analysis adjusted for age, duration of infertility, body mass index, thyroid-stimulating hormone, metabolic syndrome group, homeostatic model assessment of insulin resistance, metformin utilization, number of available embryos, and embryos transferred showed that the number of embryos transferred and the number of available embryos were positively but metabolic syndrome negatively associated with the cumulative live birth rate (odds ratio, 2.18, 1.10, and 0.70, respectively, P < .05).

Conclusion: Women with polycystic ovary syndrome with metabolic syndrome have a negative impact from female fecundity, and this suggests an adverse effect on in vitro fertilization cycle stimulation characteristics and clinical outcomes.

Keywords: cumulative live birth; female fertility; in vitro fertilization; metabolic syndrome; polycystic ovary syndrome.