Popping the pill may change whom a woman finds attractive leading to an "unnatural" selection.

Birth control pills prevent pregnancy by smoothing out a woman's hormones, and stopping ovulation.

But experts in the U.K. find that tweak also changes her preferences in men and how men view her.

Studies show ovulating women who aren't on the pill are attracted to men with masculine features and those who have a different immune system from their own which could lead to healthier children.

Research also shows men are more likely to find an ovulating woman appealing.

Study authors say they don't know what the long-term impact of the pill will be on evolution, but in the meantime, dinner and a movie can go a long way to keep our species going.