A few weeks ago, Vicki Thorn spoke at UMinnesota Duluth on “The Science of Sex” – and said some surprising things. I had never heard, until then, that oral contraceptives had any impact on people’s choice of sexual partners. She claimed that women women who ovulated naturally were attracted to a different type of man then women on the pill. Even more surprising was the statement that men, without any information about the women’s ovulation status, were more attracted to women who were not on the pill and were ovulating. The claims were interesting, but I wanted to see some scientific analysis before I would believe it.
Well, a study drawing together the results of many earlier studies was reviewed today on Science Daily, and it bears out Vicki Thorn statements. At the time they ovulate naturally, women are attracted to more “masculine” men than they are at other points in their cycle, or than women on the pill. I was skeptical – exactly how did they define “masculine” men?
Ovulating women exhibit a preference for more masculine male features, are particularly attracted to men showing dominance and male-male competitiveness, and prefer partners that are genetically dissimilar to themselves. This is significant because there is evidence suggesting that genetic similarity between couples might be linked with infertility.
Over the years, I’ve read a number of studies of the effects of testosterone on men, including their attraction to various women, so this is not so surprising. But the report goes on to confirm that men, somehow, are aware of which women are currently ovulating – and have a preference for them.
Further, some studies have suggested that men detect women’s fertility status, preferring ovulating women in situations where they can compare the attractiveness of different women.
I’m wondering if, somehow, women themselves have not developed some understanding of these effects. When the birth control pill first came out, and especially when the low-dose varieties were developed, they were tremendously popular with college-age women – without them, the sexual “revolution” of the 1960s might not have happened. They seem to be less popular now. While some young women say that it doesn’t seem natural or they don’t like the side effects, perhaps – at some level – they’ve experienced a decrease in their attractiveness when they’re on the pill and choose to go off.
Sociologists have speculated that much of the increase in infertility is related to the later age at marriage – now around 27 for men – and a variety of health factors. This research hints that some component of the infertility-boom may not be related to age, but to the whole pattern – using oral contraceptives during the many years of dating and therefore being more likely to choose a mate who is genetically similar. If that’s the case, it might also explain why even in vitro fertilization techniques are not so successful for these couples – and why donor sperm or eggs (genetically less similar) may work. I will certainly be on the lookout for more reports.
Just one more bit of evidence that there really is such a thing as “chemistry” between people!