title: [Correlation of the second to fourth digit ratio with the body mass index of infertile men].
abstract: OBJECTIVE
  To investigate the relationship between the second to the fourth digit ratio (2D:4D) and body mass index (BMI) in infertile men of the Han ethnic group in Ningxia.
  
  
  METHODS
  Using anthropometry, we calculated the mean ratio of 2D:4D and BMI of 197 infertile men and 148 normal healthy male controls, followed by analysis of their relationship.
  
  
  RESULTS
  The BMI was correlated positively with the 2D:4D ratio of the left hand in the infertile men (P < 0.05) and in the patients with a higher 2D:4D ratio of the left hand (P < 0.05), but negatively with the 2D:4D ratio of the righ/left (Dr-1) (left: P < 0.01; Dr-l: P < 0.05). The mean 2D: 4D ratio and BMI were both lower in the normal control than in the infertile men, with statistically significant differences in BMI (P < 0.05) and the 2D:4D ratio of the left hand (P < 0.05).
  
  
  CONCLUSIONS
  There is a correlation between the 2D:4D ratio and BMI in infertile men.
authors.forename: Hao-chen
authors.initials: HC
authors.lastname: Yu
authors.forename: You-jing
authors.initials: YJ
authors.lastname: Sheng
authors.forename: Zhi
authors.initials: Z
authors.lastname: Geng
authors.forename: Jun-li
authors.initials: JL
authors.lastname: Zhao
authors.forename: Jun-jie
authors.initials: JJ
authors.lastname: Liu
authors.forename: Zheng-hao
authors.initials: ZH
authors.lastname: Huo
authors.forename: Hong
authors.initials: H
authors.lastname: Lu
mesh_terms: D015992:Body Mass Index; D016022:Case-Control Studies; D005385:Fingers / Q000033:anatomy & histology*; D006801:Humans; D007248:Infertility, Male / Q000175:diagnosis*; D008297:Male