Finger Length

Andrew Huberman discussed how finger length ratios can indicate prenatal androgen exposure and its associated effects. Measurements from the base of the finger to the tip, excluding fingernails, reveal that higher prenatal androgen exposure typically leads to a longer ring finger compared to the index finger (D4 greater than D2). This pattern is generally observed more in males due to their higher prenatal exposure to androgens. Conversely, females, who are typically exposed to less androgen, often have ring and index fingers that are more similar in length. Such traits are established in utero and are indicative of primary sexual characteristics, not influenced postnatally. Interestingly, the study also explored correlations between finger length ratios and sexual preferences, suggesting that early hormonal influences might play a role in this aspect of human development 1.