Shakespeare's play explores some common sixteenth century anxieties about miscegenation (interracial sex and marriage) by examining the relationship between a black man who marries a white woman, accuses her of being unfaithful, and then strangles her on her wedding sheets. In Othello, most male characters assume that women are inherently promiscuous, which explains why all three women characters in the play are accused of sexual infidelity. It also explains, in part, why it's possible for Iago to so easily manipulate Othello into believing his wife is having an affair. Othello is also notable for its portrayal of homoerotic desire, which seems to be a factor in Iago's plot to destroy Othello and Desdemona.
In the course of the play, Iago infects Othello with his negative, crude view of sexuality.
To the men in Othello, female sexuality is a threatening force more than it is an attractive one.