Study: The female orgasm may have once served to trigger ovulation

The female orgasm, which has mystified scholars since the days of Aristotle, might have once had a hand in inducing ovulation, according to new research published Monday in JEZ-Molecular and Developmental Evolution.

Scientists at Yale University and the Cincinnati Children's Hospital took a closer look at the evolutionary development of the female orgasm in placental mammals, which are nourished inside the mother's uterus. They zeroed in on one physiological trait accompanying it, the neuro-endocrine discharge of prolactin and oxytocin, the so-called "cuddle hormone."

The research team discovered that the female orgasm may have once served a biological purpose: to trigger ovulation in many mammals.

After outgrowing its biological usefulness, the female orgasm could have adapted from its role in direct reproduction (the ancestral reflex for inducing ovulation) and instead, taken on more secondary duties.

Separately, a comparative study on female genitalia indicated that the clitoris moved from its ancestral spot (inside the copulatory canal), perhaps making it more difficult for women today to achieve orgasm.