Association between sleep and ovarian reserve in women undergoing IVF/ICSI: a Mendelian randomization and...

Sleep and circadian rhythm disruptions are recognized risk factors for impaired fertility, but their effects on ovarian reserve and underlying mechanisms remain unclear. This study aimed to evaluate the association between sleep characteristics and ovarian reserve in women undergoing in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI).

A mendelian randomization (MR) analysis of genome-wide association study (GWAS) data assessed the causal link between sleep disorders and FSH levels. A cross-sectional study was then performed to evaluate the association between sleep characteristics and ovarian reserve in women undergoing IVF/ICSI. This observational analysis included data from 1,288 IVF/ICSI patients aged 20-40 years enrolled from June 2023 to May 2024.

MR analysis of GWAS data revealed a significant association between genetically predicted sleep disorders and elevated FSH (Follicle-stimulating hormone) levels (OR = 1.259, P = 0.03). Clinical cross-sectional analyses showed that advanced age (≥35 years, OR: 1.14, 95% CI: 1.07-1.21), unemployment (OR: 0.61, 95% CI: 0.40-0.91), primary infertility (OR: 0.57, 95% CI: 0.35-0.92), sleep disturbance (OR: 2.42, 95% CI: 1.39-4.21), and shorter sleep duration (OR: 1.89, 95% CI: 1.27-2.80) were associated with diminished ovarian reserve (DOR). After adjusting for age, employment status, and infertility type, short sleep duration (6-7 hours and <7 hours) and sleep disturbances remained significantly associated with elevated FSH levels, reduced AMH (Anti-Müllerian hormone) levels, and decreased AFC (antral follicle count). Among women aged <35 years, both short sleep duration and poor sleep quality were significantly associated with DOR. In women aged ≥35 years, only poor sleep quality-not short sleep duration-was significantly associated with DOR.

Shorter sleep duration (<7 hours/night) was associated with DOR in women undergoing IVF/ICSI, particularly in those aged <35 years. In contrast, poor sleep quality adversely affected ovarian reserve regardless of age.