Are longer legs associated with enhanced fertility in Chinese women?

Female height impacts fertility differently in western and nonwestern cultures. Leg length or relatively longer legs comprise key components of height and possibly indicates mate value. We examined the associations between height, its components, and reproductive outcomes in a large Chinese cohort. Multivariable regression was used to assess the association of height, leg length (standing minus sitting height) and relatively longer legs with number of offspring in a cross-sectional sample of 9998 Chinese people aged at least 50 years from Phase 2 of the Guangzhou Biobank Cohort Study recruited in 2005–2006. Older and less educated respondents had more children. Adjusted for age, childhood socioeconomic status (SES), and education, women with longer legs had more offspring; however, there was no such association in men. When stratified by childhood SES (reported parental material possessions), longer legs and relatively longer legs were most strongly associated with more offspring in women from poorer backgrounds. Fertility was specifically associated with longer legs and relatively longer legs in women only. The difference in the association of leg length to number of offspring by childhood SES suggests a preference advantage rather than a physiological advantage in being taller. However, these benefits were specific to reproductive success in women and particularly women from poorer backgrounds suggesting that social factors may have facilitated fertility.