Sex-specific associations between psychological resilience and blastocyst quality.

ABSTRACT: Psychological resilience is an adaptive capacity that enables individuals to maintain or regain equilibrium following stress. Infertility treatment represents a significant psychological stressor for many couples. Although higher resilience has been associated with better psychological well-being in patients undergoing medically assisted reproduction, its relationship with embryological outcomes remains unknown. This study aimed to determine whether psychological resilience in couples undergoing infertility treatment is associated with blastocyst quality. In this prospective observational study, a total of 126 infertile couples who underwent intracytoplasmic sperm injections, with fresh autologous gametes, were included. Psychological resilience in both partners was assessed using the 10-item Connor-Davidson Resilience Scale. The number of mature oocytes retrieved, semen parameters, and sperm histone retention were evaluated. The primary outcome was the Day 5 good-quality blastocyst development rate. Higher psychological resilience in men, but not in women, was independently associated with a higher good-quality blastocyst development rate (B = 0.06, 95% CI 0.01-0.11, p = 0.02) and remained significant in sensitivity analyses. Male resilience was also positively correlated with sperm morphology (ρ = 0.28, p = 0.001) and inversely correlated with sperm histone retention (ρ = -0.26, p = 0.02). Psychological resilience in men, but not in women, was associated with sperm characteristics and blastocyst quality in couples undergoing infertility treatment. These findings suggest that psychological factors may be reflected in biological parameters relevant to reproduction. Further studies are needed to investigate underlying mechanisms and reproductive outcomes beyond embryo development. LAY SUMMARY: Psychological resilience is the ability to adapt to and recover from stressful situations. Infertility treatment can be emotionally challenging for couples, but it is not known whether resilience is related to laboratory outcomes during treatment. In this study, we assessed psychological resilience in 126 couples undergoing intracytoplasmic sperm injection, a fertility treatment in which one sperm is injected into each mature egg. We found that higher resilience in men was associated with better sperm characteristics and a higher rate of good-quality embryos reaching the blastocyst stage on Day 5. This association was not observed in women. These findings suggest that psychological factors in men may be linked to biological features relevant to reproduction. However, this was an observational study and cannot prove cause and effect. Larger studies are needed to confirm these findings and to understand the biological mechanisms involved.