According to new research, ovulation alters women's behaviour on a subconscious level, prompting them to focus more on social standing in comparison to other females.
Researchers from the The University of Texas at San Antonio (UTSA) and the University of Minnesota's Carlson School of Management conducted three studies, one of which featured the popular "dictator game experiment." Fifty-eight ovulating and non-ovulating women were each given a set amount of money, which they could share with another if desired. Non-ovulating women shared about 50 per cent of their money with others, while ovulating women shared about 25 per cent of funds and kept the rest.
"We found that ovulating women were much less willing to share when the other person was another woman. They became meaner to other women," said Kristina Durante, assistant professor of marketing at the UTSA College of Business and lead study author.
In another experiment, 309 women were asked to choose between "Option A" -- to have a $25,000 car while other women received $40,000 cars -- and "Option B" -- a $20,000 car while the other women received $12,000 cars. Ovulating women preferred "Option B," which provided "higher social standing" compared to the others.
"What's interesting about this finding is that ovulating women are so concerned about their relative position that they are willing to take less for themselves just so that they could outdo other women," said study coauthor Vladas Griskevicius, associate professor of marketing at the University of Minnesota's Carlson School of Management.
Ovulating women had different reactions when playing the same games against men. While ovulation seemed to make women meaner to one another, it resulted in "nicer" behaviour towards men.
"These findings are unlike anything we have ever seen in the dictator game. You just don't see people giving away more than half of their money," noted Durante. "One possibility is that we're seeing ovulating women share more money as a way to flirt with the men."
The results, entitled "Money, Status, and the Ovulatory Cycle," were published in the February issue of Journal of Marketing Research. It builds on previous studies from Durante and colleagues, including the role of ovulation in consumer choices and behaviour towards men. Such studies found that ovulation subconsciously encourages women to choose "sexier" outfits in hopes of outdoing other attractive women, and to flirt more heavily, especially with men who have assorted genetic fitness markers.
10 Things You May Not Know About Your Fertility
(01 of10)
Open Image Modal1. Your fertility is mostly determined by genetics, which influences how many eggs you are born with. Doctors believe that the number of eggs you have at birth determines the length of time you will remain fertile. At birth, women have about two million eggs in their ovaries. For every egg ovulated during your reproductive life, about 1,000 eggs undergo programmed cell death. Other things, such as smoking cigarettes and certain types of chemotherapy, can accelerate egg cell death and promote an earlier menopause.
(02 of10)
Open Image Modal2. Regular menstrual cycles are a sign of regular ovulation.Most women have regular cycles lasting between 24 and 35 days. This is usually a sign of regular, predictable ovulation. Women who do not ovulate regularly have irregular menstrual cycles. Those who do not ovulate at all may have a genetic condition called polycystic ovarian syndrome (PCOS).
(03 of10)
Open Image Modal3. Basal temperature charting does not predict ovulation.An older method of tracking ovulation involves taking your oral body temperature each morning before getting out of bed. This is called basal body temperature. This method is used to spot a rise in basal temperature, which is a sign that progesterone is being produced. The main problem with using this method is that your temperature rises after ovulation has already occurred. This makes it more difficult to time intercourse at an optimal time for conception. A better method is to use over-the-counter urine ovulation predictor test kits such as Clearblue Easy. These kits test for the hormone that prompts ovulation, which is called luteinizing hormone (LH).
(04 of10)
Open Image Modal4. Most women with blocked fallopian tubes are completely unaware they may have had a prior pelvic infection.About 10 percent of infertility cases are due to tubal disease, either complete blockage or pelvic scarring causing tubal malfunction. One major cause of tubal disease is a prior pelvic infection from a sexually transmitted disease such as chlamydia. These infections can cause so few symptoms that you may be completely unaware your tubes are affected. This is why fertility physicians will order a dye test of the tubes, called a hysterosalpingogram (HSG), if you have been trying and failing to conceive for 6 months or longer.
(05 of10)
Open Image Modal5. In most cases, stress does not cause infertility. Except in rare cases of extreme physical or emotional distress, women will keep ovulating regularly. Conceiving while on vacation is likely less about relaxation than about coincidence and good timing of sex.
(06 of10)
Open Image Modal6. By age 44, most women are infertile, even if they are still ovulating regularly. Even with significant fertility treatment, rates of conception are very low after age 43. Most women who conceive in their mid-40s with fertility treatment are using donated eggs from younger women.
(07 of10)
Open Image Modal7. Having fathered a pregnancy in the past does not guarantee fertility. Sperm counts can change quite a bit with time, so never assume that a prior pregnancy guarantees fertile sperm. Obtaining a semen analysis is the only way to be sure the sperm are still healthy!
(08 of10)
Open Image Modal8. For the most part, diet has little or nothing to do with fertility. Despite popular press, there is little scientific data showing that a particular diet or food promotes fertility. One limited study did suggest a Mediterranean diet with olive oil, fish and legumes may help promote fertility.
(09 of10)
Open Image Modal9. Vitamin D may improve results of fertility treatments. A recent study from the University of Southern California suggested that women who were undergoing fertility treatments, but had low vitamin D levels, might have lower rates of conception. This vitamin is also essential during pregnancy. At Pacific Fertility Center, we recommend our patients take 2,000-4,000 IU per day.
(10 of10)
Open Image Modal10. Being either underweight or overweight is clearly linked with lowered levels of fertility. The evidence in recent years is that obesity is clearly linked with a longer time to conception. Having a body mass index less than 18 or over 32 is associated with problems ovulating and conceiving, as well as problems during pregnancy.