According to a new study, it appears that a woman's ovulation calendar could effect how easy or difficult it is for her to quit smoking cold turkey. Adrianna Mendrek, lead researcher from the University of Montreal, said her findings emphasize the need for gender-based smoking cessation therapies that also take menstrual cycle phase into consideration.

Researchers recruited 34 chronic, but health smokers (19 women and 15 men) who weren't seeking treatment for their nicotine addiction.  Thirty to forty minutes before the experiment, they were each asked to smoke one cigarette to ensure researchers had a baseline for cigarette craving.

The researchers then placed them into an fMRI machine and asked each subject to view alternating sequences of smoking-related photos and neutral photos.  After the fMRI session, researchers showed the participants the photos again and asked them to rate them on a scale of zero to 100 in terms of how much the pictures made them want to smoke. 

Each of the 13 female participants were tested twice to capture their response at different points in their menstrual cycle that was later confirmed by blood analysis. The experiments revealed that during a woman's follicular phase (after one's period but before ovulation), seeing a cigarette and smoking imagery greatly activated five centers of the brain, indicating higher cravings.  However, during a woman's luteal phase, only one center responded with limited activation.  During this phase, a woman's body produces elevated levels of the hormones estrogen and progesterone that could be helping women fight cravings.

"Our data reveal that [uncontrollable] urges to smoke are stronger at the beginning of the follicular phase that begins after menstruation," Mendrek says. "Hormonal decreases of [estrogen] and progesterone possibly deepen the withdrawal syndrome and increase activity of neural circuits associated with craving."

Mendrek was only able to demonstrate this difference in cravings by the use of brain imagery.  She was not able to link participants' own reports of their cravings and menstrual phases. However, Mendrek still concludes that "taking the menstrual cycle into consideration could help women to stop smoking," and calls for more studies that investigate the differences in men and women when it comes to smoking and addiction.

According to the World Health Organization, smoking kills five million people globally each year.  In high-income countries, the rates of smoking between men and women are almost equal, but it is estimated that in many low and middle-income countries, the smoking rate of women will rise to match the rate of men.