Association of chronotype and depressive symptoms in Chinese infertile population undergoing assisted reproductive technology

Objective: To assess the association between chronotype and depressive symptoms in an infertile population undergoing assisted reproductive technology. Design: Cross-sectional study. Setting: The First Affiliated Hospital of Anhui Medical University Reproductive Medicine Center in Hefei, China. Population: 1022 infertile patients who sought assisted reproductive technology at the Center between August and October 2022, were assessed for inclusion in this study. Methods: On the day of ovulation injection, we collected socio-demographics by inviting infertile patients to complete questionnaires and assessed the subjects’ chronotypes through the Morning and Evening Questionnaire-5 Items (MEQ-5). Main Outcome Measures: Depressive symptoms, assessed with validated Patient Health Questionnaire-9 (PHQ-9) and expressed as PHQ-9 scores. Results: Overall, 9%, 68%, and 22% of participants were categorized as evening, neutral, and morning chronotypes, respectively. There were significant differences between chronotype on levels of depressive symptoms, subjects with morning chronotype (odds ratios = 0.32, 95% confidence intervals: 0.18-0.57) and neutral chronotype (odds ratios = 0.47, 95% confidence intervals: 0.28-0.77) had lower odds of depressive status, compared to those with evening chronotype, but no partner effect of chronotype was found ( p >0.05, respectively). Conclusions: Our findings suggest that morning and neutral chronotypes may be significantly associated with a lower likelihood of depressive symptoms. In addition, the effect of earlier chronotypes in men on depressive symptoms in women warrants relevant clinical attention when considering treatment.