Association of relative fat mass with female infertility: a cross-sectional study based on NHANES 2017-2020

Relative Fat Mass (RFM) is an emerging body fat measurement index that more accurately reflects the distribution of visceral fat. This study aimed to investigate the association between RFM and female infertility. We utilized data from the National Health and Nutrition Examination Survey (NHANES) spanning from 2017 to 2020, enrolling 1487 female participants aged 20-44. The relationship between RFM and infertility was analyzed using multivariate Logistic regression, and the dose-response relationship was assessed with Restricted Cubic Splines (RCS). The study found a significant association between RFM and infertility. After adjusting for confounders such as age, ethnicity, and BMI, each unit increase in RFM was associated with a 6% increase in the risk of infertility (OR = 1.06, 95%CI = 1.01-1.12, P = 0.019), with stable results across different subgroups. RFM is significantly associated with female infertility and may serve as a useful tool in infertility screening. Future studies should further validate its potential for clinical application.