NEW YORK (Reuters) -- Cigarette smoking can have adverse effects on a woman's menstrual periods, according to a report in the March issue of the journal Epidemiology.
At the University of Virginia, Charlottesville, Dr. Paige P. Hornsby and colleagues found that compared with nonsmokers, smokers experienced more days of pain before and during their periods.
The study also showed that the women who smoked most reported the most days of pain. Smokers had shorter periods than nonsmokers, but they bled more heavily on the first two days.
Hornsby's team asked 358 women, ages 37 to 39, to keep a menstrual diary for six months. In this group, 275 women were nonsmokers, 35 were light smokers, and 48 smoked more than half a pack of cigarettes per day.
"Biological mechanisms for the effects of smoking on menses are not clear," Hornsby and her colleagues comment. Some theories advanced by other researchers are that cigarette smoke is toxic to the ovaries, that smoking changes the way the central nervous system regulates hormones, and that smoking inhibits the production of estrogen.
SOURCE: Epidemiology (1998;9:193-198)
