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2D:4D finger length ratio and reproductive indices in a Chuvashian population
Leonid Kalichman1, Valery Batsevich, Eugene Kobyliansky
1Department of Physical Therapy, Recanati School for Community Health Professions, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel.
Objective:
to evaluate the association between 2D:4D finger length ratios (representing the prenatal environment, i.e., early androgen exposure) and reproductive indices, such as age at menarche, menopausal age, and length of reproductive period.
Methods:
Retrospective data on age at menarche and menopausal age as well as x-rays of both hands were obtained from 674 Chuvashian women aged 18-70 years (mean 46.32 ± 15.42). Finger and metacarpal length ratios as well as visual classification of finger ratio types, were estimated from the x-rays.
Results And Conclusions:
We found that a low 2D:4D ratio (radiologically evaluated), a masculine 2D:4D ratio type (visually evaluated), and a putative bioassay for prenatal androgen exposure, were associated with a later menarche and a shorter reproductive period. No association was found with menopausal age.
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