The XX Factor

The Many Ways the Pill Could Do You Wrong

If the blood clots and stroke risks don’t scare you off the pill , maybe this will: Women taking oral contraceptives are less attractive to the opposite sex and less likely to pick a good mate, according to a roundup of studies on the pill , published in this month’s Trends in Ecology and Evolution , that Sarah Kliff at Newsweek reported on today.

When a woman is ovulating, her hormonal fluctuations affect her “facial appearance, her vocal pitch, even body odor,” Kliff writes. “And during ovulation, those changes increase a woman’s attractiveness because they indicate fertility.” Hardly as dramatic as the potential side effect that terrified many of my friends when we started going on the pill: rapid weight gain. But apparently men-who, so the legend goes, don’t even notice a new outfit or restyled hair (or is that just my dad?)-pick up on these shifts, as shown in a study in the roundup that found that lap dancers make higher tips when they’re ovulating.

The pill’s influence on scent goes both ways: Women on the pill react differently to men’s scents, too-in a way that might be leading us toward the wrong guys. One study in this month’s report found that women on the pill are more likely to be attracted the smell of genetically similar guys . (More impressive than the study’s findings, perhaps, is that the researchers “collected body odor from volunteers and put it in jars for the ladies to smell.” Sucks to be that research assistant.) That means that pill-popping women may be selecting partners counter to the credo that the species is stronger if we mate with people who are genetically dissimilar (put in simpler terms, “opposites attract”).

I imagine that the more tangible threats of weight gain, loss of libido, and mood swings will remain the only pill side effects that actually keep people away. Still, these studies are going to stick with me for a while, if only for the imagery of menstruating lap dancers and smells in jars.

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