The female reproductive cycle is an awesome force of nature. Men – single, dating or married – ignore it at their own sexual peril. A man who is in tune with what a woman’s body wants is a man who will seldom lack for companionship.

You ignored it in junior high health class. You begrudgingly accepted it during every relationship you’ve ever been in. Let’s talk about it – the female reproductive cycle, your new best friend.

The Facts

There are four phases in the female reproductive cycle: the menstrual phase, the follicular phase, the ovulation phase and the luteal phase. The list below shows the days of the phases. Keep in mind that a woman is most likely to become pregnant between day 12 and day 16.

Day 0-5: the menstrual phase (stay away phase)
Day 6-14: the follicular phase (nothing to see here phase)
Day 14 (approximately): the ovulation phase (peak horniness phase)
Day 15-28: the luteal phase (looking for a nice guy phase)

Gordon Gallup, a professor at the University of Albany, discussed the female menstrual cycle in his study “The Science of Sex Appeal: An Evolutionary Perspective.” He found that when women ovulate and enter estrus they encounter a period (no pun intended) of heightened interest in or receptivity to sex, specifically with males displaying traits linked to testosterone or dominance status. “If a woman is fertile, she’s looking for the best genes for her offspring,” explains Randy Thornhill, a distinguished professor of biology at the University of New Mexico. “She’s more likely to be attracted to socially dominant men and more likely to pay closer attention to testosterone.”

It’s important to keep in mind that this is only true for women who ovulate.

“Women who take the pill do not ovulate,” Thornhill notes. “Hence, oral contraception eliminates the estrus, and we haven’t seen a change in behavior for these women.”

What This Means for You

This is all well and good, but can it benefit you? Abso-freakin’-lutely. “The more men know about women, the more they can enjoy women,” Thornhill points out. “That’s sort of flawless. The more you know about any subject, the better off you are.” Bottom line: stop cringing at the thought of ovulation and listen up.

Women’s preferences in male partners can and will change during ovulation. Studies show that a woman finds less-masculine qualities such as soft features, less-defined body and overall gentler style and voice more attractive in her luteal phase.

When women are fertile and capable of becoming pregnant, they tend to gravitate toward “masculine” men – leaner bodies, squarer chins, heavier eyebrows, lower voices.

“What we see and what is interesting is that guys who are seen as these stable providers, reliable guys, good for a long-term relationship, low risk-takers and high investors in offspring are what women desire when they are not at their fertile period,” says Daniel J. Kruger, P.h.D. a research professor at the University of Michigan who studies evolutionary psychology.

But what happens when they are fertile and capable of conception?

“There is a shift,” said Kruger, “to guys with genetic investments, guys who are a good match for the genetic environment, who lack harmful mutations, have strong physiology, high levels of testosterone, guys who are physically fit and attractive in a masculine way.

In other words, chicks dig Jason Statham when they’re fertile, and Seth Rogen when they’re not.

“It’s ironic that women tend to lean towards the socially dominant, high status, physically attractive type when they are fertile even though these men are possibly less likely to be around to raise the kid. A lot of times, we see these desired types of guys shifting to their own mating strategies, which allows them to engage with many women to heighten their chances of producing offspring.”


Use This Information Wisely

Kruger says that men could strategically use this information to maximize their own efforts for attracting women — even in their current relationships. If you know that your girl is ovulating, you could plan in advance to do something exciting. At this time of the month, females prefer adventure and risk-taking. Try something new like a short trip or a daytime activity that she considers thrilling.

Female ovulation and monthly shifts in hormones affect both men and women. In addition to a change in a woman’s preference in male partners, women who are ovulating are more likely to find themselves more attractive. When asked by researchers, women who were ovulating felt that they were sexier and more desirable to men than women who were not ovulating.

Men agree. Gallup’s study notes that men rated female faces more attractive when they were in their ovulatory phase. Their waist-to-hip ratio became accentuated, their breasts were more symmetrical and their body and vaginal odors were rated as being more pleasant. In fact, women who are ovulating try to look sexier in public. They are more likely to wear miniskirts and show more skin at this time of the month. Consequently, these women were more likely to be receptive to men’s advances in a social setting. A woman who is ovulating is probably more likely to accept your invitation on a date.

“We say that human ovulation is partially concealed,” explains Kruger. “It’s definitely not as obvious like it is with baboons and other species who visibly change during ovulation.”

Clearly Kruger has never seen an episode of Jersey Shore.

Research has revealed how female behaviors and desires change during ovulation and how you, as a man, can appropriately use this information. Next time you’re at the bar and you see a woman showing off those perfectly symmetrical breasts, and drawing attention to herself in even less-subtle ways, approach her as the masculine man you are. With any luck, science and nature will combine to produce a very fruitful night for you.

(Alexandra Foster writes about women and relationships for Made Man.)