The Association Between Paternal BMI and Semen Quality in Cohorts Undergoing IUI, IVF and ICSI Fertility Treatments: A Systematic Review and Meta‐Analysis

Background The prevalence of obesity and overweight in reproductive age shows an upward trend globally, impacting fertility potential. Against this backdrop, infertility affects an estimated 17.5% of the global population. Intrauterine insemination (IUI) and assisted reproductive technology (ART) are advanced options in a structured fertility care pathway and ensuring semen quality remains a critical step in guiding fertility treatment decisions of these cohorts. Contradictory reports about the impact of paternal body mass index (BMI) on semen quality in these procedures necessitate confirmation of this influence. Objectives To critically analyse the literature and synthesise evidence on the impact of paternal BMI on semen quality among those seeking IUI or ART. Materials and Methods Systematic search in four databases: ‘PubMed’, ‘Web of Science’, ‘Embase’ and ‘Scopus’ was performed on 28th September 2025. Studies reporting comparison of semen parameters between BMI categories among IUI and ART cohorts were included and interventional studies were excluded. The pooled estimate of mean difference, 95% confidence interval (CI), prediction interval, I 2 value, LFK, were estimated and Age and BMI classification sub‐group analysis were performed. Risk of bias was assessed using ‘JBI Cross‐sectional tool’. Results Twenty‐two studies qualified for meta‐analysis out of 34 included studies. The sperm total motility showed a statistically significant pooled mean difference −8.17 between the overweight and normal group with 95% CI = −15.15 to −1.20. Subgroup analysis as per BMI classification showed significant differences in sperm concentration between the overweight and normal groups (test for subgroup differences, p = 0.0206). Prevalence of paternal obese and overweight is 12.15% and 43.37% respectively. Conclusion Paternal obesity showed no significant association with semen parameters. However, paternal overweight had significant effect on total motility. Further studies on the impact of paternal BMI using novel anthropometric measures, ruling out metabolic and lifestyle factors on semen are warranted.