Science people sez

Study 1

Men's masculinity and attractiveness predict their female partners' reported orgasm frequency and timing

and

Study 2

Women with partners possessing low fluctuating asymmetry and their partners reported significantly more copulatory female orgasms that were reported by women with partners possessing high fluctuating asymmetry and their partners, even with many potential confounding variables controlled.

So the solution is for women who feel they're getting the "short end of the stick" is to simply increasingly pick attractive, masculine, symmetrical men to sleep with.

Boom. Orgasm gap solved. Where dafuq my nobel prize at