A new study shows that young women in relationships may dress a bit more enticingly as they reach the ovulation phase of their monthly fertility cycle — the time when they are most fertile.
The 30 college women studied were more likely to wear lace-trimmed tops, skirts instead of pants, and more revealing (though still appropriate) clothes as they neared ovulation, when an egg is released from the ovary.
Researchers included Martie Haselton, PhD, of UCLA, and April Bleske-Rechek, PhD, of the University of Wisconsin-Eau Claire.
The study is due for publication online in Hormones and Behavior.
Dressing to Impress
"Near ovulation, women dress to impress, and the closer women come to ovulation, the more attention they appear to pay to their appearance," Haselton says in a UCLA news release.
"They tend to put on skirts instead of pants, show more skin, and generally dress more fashionably," Haselton adds.
The 30 women in Haselton's study were UCLA undergraduates and 21 years old, on average.
All said they were in relationships, had regular menstrual cycles, and weren't using hormonal contraceptives.
The women took urine tests to gauge where they were in their cycle. They were also photographed twice -- once on a high fertility day and once on a low fertility day.
The women didn't know what the study was about.
The photos weren't glamour shots. The women simply stood in front of the same background both times with their hands at their sides.
Trying to Look Good?
The researchers showed the women's photos to 37 judges -- 17 men and 25 women -- at UCLA and the University of Wisconsin-Eau Claire.
Most of the judges were 18-23 years old; the two oldest were 41 or older.
The judges reviewed each woman's set of photos, with the near-ovulation and far-from-ovulation pictures shown side by side.
The women's faces were covered in the photos so the judges could focus on their clothes, jewelry, and hairstyle.
The researchers asked the judges: "In which photo is the person trying to look more attractive?"
In almost six out of 10 cases, the judges chose the photo in which the woman was more fertile.
The closer a woman was to ovulation when the photo was taken, the more likely the judges were to pick that photo as the one in which she was "trying to look more attractive."
What the Women Wore
The researchers describe some of the outfits from the "high fertility" photos.
"For example, two women who dressed similarly in each session wore tops with lace trim at high fertility; three wore skirts instead of pants; one woman added a fringy neck scarf; and several women simply showed more skin," the researchers write.
Not exactly a wild transformation.
"Although women revealed more skin, clothing choices were not coded as 'sexier' at high fertility, which could reflect the norms of daytime student dress, in which sexually explicit clothing is not appropriate," the researchers write.
"Alternatively, the effect we have documented might reveal a general desire to look more attractive rather than to appear 'sexy,'" they say.
"The thing that's so remarkable about this effect is that it's so easily observed," Bleske-Rechek says in a news release.
But the reasons for the style shift aren't clear.
What a woman wears is not just about hormones. Her mood and schedule may also affect clothing choices.
For instance, a woman would likely dress differently if she's dashing across campus for an exam rather than going to a job interview, the researchers note.
Interestingly, no style changes were linked to PMS.
"The approach of ovulation had a much stronger impact on the way women dressed than the onset of menstruation," Bleske-Rechek says.
"There's a popula notion that when women approach menstrual onset, they get out their bloated clothes and they pull out their sweats," Haselton explains.
"So if what we were measuring was a PMS effect, you'd expect that if a woman has her photo taken one or two days before menstrual onset, then she's going to dress frumpier than someone who had her photo taken 10 days before menstrual onset. But we didn't find that to be the case," Haselton says.
SOURCES: Haselton, M. Hormones and Behavior, Oct. 10, 2006; online edition. News release, UCLA.
By Miranda Hitti
Reviewed by Louise Chang