Is cunnilingus-assisted orgasm a male sperm-retention strategy?

We secured data from 243 men in committed, sexual, heterosexual relationships to test the sperm retention hypothesis of oral sex. We predicted that, among men who perform cunnilingus on their partner, those at greater risk of sperm competition are more likely to perform cunnilingus until their partner achieves orgasm (Prediction 1), and that, among men who ejaculate during penile-vaginal intercourse and whose partner experiences a cunnilingus-assisted orgasm, ejaculation will occur during the brief period in which female orgasm might function to retain sperm (Prediction 2). The results support Prediction 1 but not Prediction 2. We discuss limitations of the current research and discuss how these results may be more consistent with alternative hypotheses regarding female orgasm and oral sex.