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An experimental test of the ovulatory homolog model of female orgasm.

ABSTRACT: The ovulatory homolog model of female orgasm posits that the neuro-endocrine mechanisms underlying female orgasm evolved from and are homologous to the mechanisms mediating copulation-induced ovulation in some mammals. This model predicts that pharmacological agents that affect human orgasm, such as fluoxetine, should also affect ovulation in animals with copulation-induced ovulation, such as rabbits. We tested this prediction by treating rabbits with daily doses of fluoxetine for 2 wk and found that fluoxetine treatment reduces the number of ovulations postcopulation by 30%. In a second experiment we tested whether this result was mediated by an effect on the brain or via peripheral serotonin functions. We treated animals with fluoxetine and induced ovulation with a single injection of human chorionic gonadotropin. In this experiment ovulation rate was nominally reduced by only 8%, which is statistically not significant. We conclude that the effect of fluoxetine on copulation-induced ovulation rate supports the ovulatory homolog model of female orgasm, suggesting that female orgasm has very deep evolutionary roots among the early eutherian mammals.

SUBMITTER: Pavlicev M

PROVIDER: S-EPMC6789565 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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An experimental test of the ovulatory homolog model of female orgasm.

Pavlicev Mihaela M Zupan Andreja Moset AM Barry Amanda A Walters Savannah S Milano Kristin M KM Kliman Harvey J HJ Wagner Günter P GP

Proceedings of the National Academy of Sciences of the United States of America 20190930 41

The ovulatory homolog model of female orgasm posits that the neuro-endocrine mechanisms underlying female orgasm evolved from and are homologous to the mechanisms mediating copulation-induced ovulation in some mammals. This model predicts that pharmacological agents that affect human orgasm, such as fluoxetine, should also affect ovulation in animals with copulation-induced ovulation, such as rabbits. We tested this prediction by treating rabbits with daily doses of fluoxetine for 2 wk and found ...[more]

PMID: 31570579

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An experimental test of the ovulatory homolog model of female orgasm.

Publications

An experimental test of the ovulatory homolog model of female orgasm.

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