Study: Cigarette Smoking May Worsen PMS

Here's another reason not to smoke, if you're a woman: PMS.

Women 27 to 44 years old who smoke are twice as likely to develop premenstrual syndrome over the next two to four years, especially hormonally-related symptoms like backaches, bloating, breast tenderness, and acne, Dr. Elizabeth R. Bertone-Johnson of the University of Massachusetts in Amherst and her colleagues found.

"Our findings lend further support to the idea that smoking increases the risk of moderate to severe PMS, and provides another reason for women, especially adolescents and young women, not to smoke," Bertone-Johnson told Reuters Health via E-mail

Up to 20 percent of women have PMS severe enough to affect their relationships and interfere with their normal activities, Bertone-Johnson and her team note in the American Journal of Epidemiology. Smoking has been shown to affect levels of several different hormones, and the handful of studies looking into PMS and smoking have suggested that women with the syndrome are more likely to be smokers, the researchers add.

To investigate the relationship further, they analyzed data from the Nurses' Health Study II, which has been following 116,678 US registered nurses since 1989. The researchers looked at a subset of women who were PMS-free during the first two years of the study, comparing 1,057 who did go on to develop PMS to 1,968 who did not.

The women who were current smokers were 2.1 times as likely as non-smokers to report PMS within the next two to four years, the researchers found. The risk increased with the amount they smoked, and women who had picked up the habit in adolescence or young adulthood were at even greater risk; those who had begun smoking before their 15th birthday, for example, were 2.53 times as likely to develop PMS.

"Our findings do not suggest that this is entirely due to the fact that women who start smoking at younger ages smoke for more years than those starting when they are older. Additional research on the impact of smoking at different times in women's lives is needed," Bertone-Johnson said.

She continued: "Previous studies suggest that smoking may alter levels of estrogen, progesterone, testosterone, and other hormones, many of which may be involved in the development of PMS. Some studies have found that smokers have shorter and more irregular menstrual cycles than non-smokers. Smoking may also lower levels of vitamin D in the body, which also may increase a woman's risk of developing PMS."

A 2005 study found that 26 percent of female 12th-graders had smoked on at least one of the previous 30 days, Bertone-Johnson and her team note in their report. "Given the high prevalence of this behavior in young women," they say, "these findings may provide additional incentive for young women to avoid cigarette smoking."