Association of pre-treatment sleep characteristics with reproductive outcomes among women undergoing assisted reproductive technology: a retrospective cohort study

Objective To investigate the associations between pre-treatment sleep characteristics and reproductive outcomes in infertile women undergoing assisted reproductive technology (ART) and to explore whether embryo development may represent a potential pathway linking sleep characteristics with cumulative live birth. Methods In this retrospective cohort study, pre-treatment sleep characteristics before ovarian stimulation were assessed using the Pittsburgh Sleep Quality Index (PSQI). The primary outcome was cumulative live birth, while secondary outcomes included embryo developmental parameters. Associations with ovarian reserve indicators were also evaluated. Multivariable regression, restricted cubic spline, exploratory mediation, and sensitivity analyses were performed. Results In an analysis of 11,090 included oocyte retrieval cycles, women with very poor sleep quality had a lower 1-year cumulative live birth rate (CLBR) (RR = 0.927, 95% CI: 0.881–0.977, P = 0.004). Sleep duration of 5 to less than 6 hours significantly reduced both 1-year (RR = 0.788, 95% CI: 0.737–0.843, P < 0.001) and 2-year CLBR (RR = 0.798, 95% CI: 0.748–0.852, P < 0.001). Furthermore, severe impairment in sleep efficiency, severe sleep disturbances, and severe daytime dysfunction were associated with lower CLBRs (P < 0.05). Secondary outcomes showed that poor sleep quality, short sleep duration of less than 5 hours, and use of sleeping medication 1–2 times per week correlated with lower available embryo rates (P < 0.05). Very bad subjective sleep quality was associated with an increased slow-cleaving embryo rate and high fragmentation rate (P < 0.05). Restricted cubic spline analyses suggested non-linear associations between sleep characteristics and ovarian reserve indicators. Exploratory mediation analyses suggested that embryo development may partially explain the associations of very bad subjective sleep quality and mild impairment in sleep latency with CLBRs. Conclusion Poor sleep quality was associated with lower cumulative live birth outcomes and poorer cleavage-stage embryo development among women undergoing ART. Exploratory mediation analyses suggested that embryo development may partially explain the observed associations between sleep characteristics and CLBRs. As a potentially modifiable factor, sleep characteristics may represent an important consideration in optimizing reproductive care, although further prospective studies are needed.