The Use of 2D: 4D Digit Ratio as a Predictor of Androgenetic Alopecia: A Review

Androgenetic alopecia (AGA) is a common hair loss condition that impacts both men and women. Age and genetic susceptibility are recognized as potential risk factors for developing AGA. The second to fourth digit ratio is a measurement of the length ratios between the index and ring fingers. This ratio has been utilized as a predictor for multiple hyperandrogenism-related medical conditions. More recently, the 2D:4D ratio was investigated as a predictor for AGA. This article will examine the evidence supporting this relationship, discuss its diagnostic implications, and identify potential areas for future research.