In the study, researchers from the University of British Columbia asked 124 women ages 18 to 47 what color shirt they were wearing, and when they had had their last period.
After calculating peak fertile days for each woman, the researchers found an association with red and pink shirts and fertility, the New York Daily News reported.
According to the report, the researchers plan to conduct a follow-up study to further ask women why they selected a particular color on the day of the survey.
Possibilities include that women feel sexier at peak fertility and want to grab more attention, consciously or unconsciously, the researchers said.
The study is set to be published in the journal Psychological Science.