WASHINGTON - Women dress to impress when they are
at their most fertile, U.S. researchers said on Tuesday in a study they say
shows that signs of human ovulation may not be as mysterious as some scientists
believe.
A study of young college women showed they frequently wore more fashionable
or flashier clothing and jewelery when they were ovulating, as assessed by a
panel of men and women looking at their photographs.
"They tend to put on skirts instead of pants, show more skin and generally
dress more fashionably," said Martie Haselton, a communication studies and
psychology expert at the University of California Los Angeles who led the study.
Writing in the journal Hormones and Behavior, Haselton and colleagues said
their findings disproved the conventional wisdom that women are unique among
animals in concealing, even from themselves, when they are most fertile.
Some animals release powerful scents when ready to mate, while others display
skin color changes, but human ovulation is notoriously difficult to detect. This
is attested to by the frequency of unintended pregnancy, as well as test kits
marketed to women wishing to become pregnant but unaware of the likeliest time
to conceive.
Haselton's team said their study showed the cues are there, even if men and
women are not consciously aware of them.
Women usually ovulate on the 15th day of their menstrual cycles, and this day
is when they are the most fertile. Ovulation is easily detected using urine
tests, and Haselton's team used such a test to check fertility in their study.
They asked 30 university students to come to their lab for a test, without
letting them know the nature of the experiment. "We asked them some things about
food, for example," Haselton said in a telephone interview.
The women came back several times over the course of a month and were
photographed twice -- once in their fertile phase and another time in their
least-fertile phase. The faces in the photographs were blacked out.
WHO LOOKS HOT?
The researchers asked 42 men and women, some older than the volunteers, to
assess these photographs by asking, "In what photo is the person trying to look
more attractive?"
The judges chose the photograph taken during the women's fertile phases 60
percent of the time, Haselton said. "This is well beyond chance. They were
pretty consistent," she said.
"One of the things we found pretty interesting is that people sort of have
their personal style, almost like their uniform," she added. "The women would
show up to the lab wearing something pretty close to what they wore before, but
embellished."
For example, one woman wore loose knit leggings and a tank top in both
photos. "In her high fertility photograph, she would be wearing a very pretty
tank top and she was wearing more jewelery. The difference was quite subtle,"
Haselton said.
The fertile women did not necessarily dress more provocatively, Haselton
noted. "We did see a little bit more skin. It was my impression that the women
were just dressing a little bit more fashionably but not sexier."
Haselton also was interested to note what did not happen.
"There's a popular notion that when women approach menstrual onset, they get
out their bloated clothes and they pull out their sweats," she said. "But we
didn't find that to be the case."
Haselton's team had earlier reported that women were more likely to flirt and
look at attractive men when ovulating.
