Digit-Length Ratios (2D:4D) as a Phenotypic Indicator of In Utero Androgen Exposure Is Not Prognostic for Androgenic Alopecia: A Descriptive-Analytic Study of 1200 Iranian Men
June 2016
in “
Dermatology Reports
”
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TLDR Finger length ratios don't predict baldness in men.
In 2016, a descriptive-analytic study was conducted on 1200 Iranian men to investigate the relationship between digit-length ratios (2D:4D) as an indicator of in utero androgen exposure and the development of androgenic alopecia (AGA). The study found no significant association between right 2D:4D and AGA severity within the entire population (P=0.384, r=0.025), although a positive correlation coefficient was identified in subjects above the age of 40. However, based on the receiver operating characteristic curve analysis, 2D:4D does not predict the development of AGA. The study concluded that AGA is a multifactorial disease and increased in utero exposure to androgens does not predispose men to develop AGA.