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The study explored whether women’s hair traits—specifically length and perceived quality—are associated with increased sexual frequency in married couples. In a survey of 204 heterosexual married dyads from South Korea, the researchers measured hair length and quality, partner attractiveness ratings, sexual desire, and frequency of intercourse, while controlling for age, relationship and sexual satisfaction, commitment, marriage duration, and number of children.

Frontiers

The analyses using a dyadic mediation model found that wives’ hair quality and length indirectly predicted higher sexual frequency through increasing husbands’ ratings of their wives’ attractiveness and consequently the husbands’ sexual desire. The direct effects of hair traits on frequency were weaker and marginal. In contrast, husbands’ hair length or quality showed no significant relationship with sexual frequency.

Frontiers

The authors interpret this as evidence that women’s hair—particularly its health/quality—may act as a subtle cue in long‐term romantic relationships, enhancing sexual signaling and pair bonding. However, they caution that the effect sizes are small, the study is cross‐sectional (so causality is uncertain), and future work should refine measurement of hair traits and examine variation across cultures and life stages.