HORMONES: “A study claims sex hormones in the contraceptive Pill bring out the green-eyed monster, making a woman more possessive and more likely to fret about her husband or boyfriend’s fidelity.” “It seems that women, and perhaps pharmaceutical providers, are not fully aware of the range of potential psychological side-effects associated with pill use and more specifically brand choice.” Well, the Pill mimics pregnancy, and there’s solid evolutionary reason for a pregnant women to be more possessive.