Abstract
STUDY QUESTION: Does preconception mental health status in either partner affect fertility and infertility, and is this association modified by socioeconomic status (SES)? SUMMARY ANSWER: Preconception mental health problems in both partners are associated with lower couple fertility, with the synergistic impact being most pronounced among couples with low SES status. WHAT IS KNOWN ALREADY: Mental health problems are rising among young adults, and fertility rates are declining. Women's preconception mental health has been linked to lower fertility, but few studies have examined the combined impact of both partners' mental health. The modifying role of SES in these associations is also poorly understood. STUDY DESIGN SIZE DURATION: This couple-based prospective cohort study included 966 preconception couples who sought preconception care and were followed for 12 months in the Shanghai Birth Cohort between 2013 and 2015. PARTICIPANTS/MATERIALS SETTING METHODS: The couples' mental health status was evaluated at enrolment using the Center for Epidemiological Studies-Depression Scale, Zung Self-Rating Anxiety Scale, and Perceived Stress Scale. The outcomes included couple fecundability (measured by the TTP) and infertility (i.e. TTP >12 menstrual cycles). In the partner-specific model, Cox proportional hazards models and logistic regression were used to evaluate the associations between each partner's depression, anxiety, and stress levels and couples' fertility. In the couple-based model, cross-classification and quantile g-computation were first applied to identify couples' joint exposure to specific psychological conditions in relation to fertility. Latent profile analysis (LPA) was then conducted to characterize distinct latent profiles of couples' overall mental health statuses, followed by Cox proportional hazards models and logistic regression to examine the corresponding associations. Key symptoms in the couples' depression, anxiety, and stress scales were determined by elastic net regression and least absolute shrinkage and selection operator. To assess the potential effect modification of SES on the association between couples' mental health and fertility, we conducted stratified analyses by male and female partner education levels and household income. MAIN RESULTS AND THE ROLE OF CHANCE: In the female partner-specific model, a 1 SD increase in depression score was associated with 10% lower fecundability (FOR = 0.90, 95% CI: 0.82, 0.99). Likewise, a 1 SD increase in the stress score was associated with 13% lower fecundability (FOR = 0.87, 95% CI: 0.79, 0.96). Male anxiety was associated with a higher risk of infertility (OR = 1.19, 95% CI: 1.01, 1.42). Stratified analyses showed that depression, anxiety, and stress were significantly associated with lower fecundability among males with an education level