Background: Growing evidence suggests that education, socioeconomic status, and leisure sedentary behaviors are associated with female infertility. However, it remains uncertain whether these connections are causally related.
Methods: Genetic variants from genome-wide association studies (GWAS) of education, socioeconomic status, and leisure sedentary behaviors were obtained from the UK Biobank and EBI database. Summarized GWAS data of female infertility were also acquired from the FinnGen Biobank Analysis. Univariable and multivariable MR analyses were performed to explore the relationships between education, socioeconomic status, leisure sedentary behaviors and female infertility. The primary analysis utilized inverse variance weighting, while alternative Mendelian Randomization (MR) methods such as MR-Egger, weighted median, and weighted mode estimate, along with Cochrane’s Q test, MR-Egger intercept test, MR pleiotropy residual sum and outliers (MR-PRESSO) test, and leave-one-out analysis were employed to evaluate sensitivity and heterogeneity.
Results: The results of the univariate MR analysis indicated that age of full- time education had a protective effect on female infertility (odds ratio [OR] 0.471; 95% confidence interval [CI] 0.24 to 0.93; p = 0.03). However, no causal correlation was found between educational attainment (college completion and years of education), socioeconomic status (job involving heavy manual or physical work, average total household income before tax, and Townsend deprivation index at recruitment), leisure sedentary behaviors (leisure social activities at pubs or social clubs, time spent driving, time spent using a computer, and time spent watching television) and female infertility. Multivariable MR and reverse MR studies did not support the existence of a relationship between education, socioeconomic status, leisure sedentary behaviours and female infertility. No significant heterogeneity or horizontal pleiotropy was detected, and the stability of the results was confirmed through sensitivity analysis and the leave-one-out test.
Conclusions: Age at completion of full-time education may be causally related to a reduced risk of female infertility.