Women are especially in need of tobacco regulation because tobacco smoke contains toxic
chemicals that can interfere and even damage reproductive capabilities. Two researchers from
Kansai Medical University and Otemae University in Japan examined how tobacco smoke
exposure affected women’s menstrual cycles.

May 15, 2021

By: Leta Dickinson

This National Women’s Health Week, we at the Thirdhand Smoke Resource Center join the US
Department of Health and Human Services’ Office on Women’s Health in encouraging all
women to protect their lung health and quit smoking and vaping. Even women that are not active
smokers can still be exposed to the chemicals in tobacco and marijuana products through toxic
second- and thirdhand smoke.

The Thirdhand Smoke Resource Center invites you to support women’s health by working to
strengthen clean air laws to include prevention of second- and thirdhand tobacco smoke
exposure. Of all the harmful environmental toxins we are exposed to on a regular basis, exposure
to tobacco byproducts is one of the easiest to prevent by explicitly prohibiting all types of
tobacco and marijuana product use in and around indoor spaces and educating the public and
policymakers about the long-lasting effects of thirdhand smoke.

Women, in particular, benefit from tobacco regulation. Tobacco smoke contains toxic chemicals
that can interfere and even damage reproductive capabilities, particularly in women. Previous
studies have found that women that actively smoke have altered hormone levels and more severe
menstrual side effects like cramping and premenstrual syndrome—commonly known as PMS.
But what about passive tobacco smoke exposure? Two researchers from Kansai Medical
University and Otemae University in Japan examined how first-, second-, and thirdhand smoke
exposure affected women’s menstrual cycles.

The researchers surveyed 5,000 women recruited from beauty salons in Osaka City, Japan about
their exposure to tobacco smoke as well as about their menstrual cycle length and symptoms.
After narrowing down survey respondents to just those women of reproductive age (20-44) who did not take oral contraceptives or medication during menstruation, the researchers grouped the
women into three exposure categories: “nonsmokers” who had never smoked, “smokers” who
had been smoking for at least a year, and “past smokers” who had smoked but quit at least one
year ago. “Nonsmokers” were further subdivided into those with no reported exposure to second-
or thirdhand smoke, those exposed to second- and thirdhand smoke in the last year, and those
that were exposed in the past but had not been for at least a year.

The researchers found that tobacco smoke had a clear effect on the regularity and discomfort of
menstruation. Current smokers were the most likely to have menstrual cycles of irregular length,
followed by nonsmokers with past exposure to second- or thirdhand smoke and past smokers.
These three groups of women all had cycles on average a day shorter than nonsmokers with no
exposure or current exposure. Shorter menstrual cycles are reflective of abnormal hormone
levels, indicating that even passive exposure could affect reproductive hormones. Of the women
who were nonsmokers, those that reported current tobacco smoke exposure also reported more
menstrual symptoms than those that were not exposed. In fact, the group of women that had the
fewest symptoms of any group were the nonsmoker, nonexposed women.

These findings demonstrate that exposure to tobacco smoke chemicals has an adverse effect on
the reproductive system, increasing the unpleasant side effects and the frequency of menstrual
cycles. It should be noted, however, that self-reported exposure to second- and thirdhand smoke
can be unreliable, especially because survey respondents may not be well informed about how
and where they may be exposed and may inaccurately recall incidences in the last year.
Additionally, Japan has long struggled with high rates of tobacco use and a lack of clean air
legislation, meaning that more likely than not, all the surveyed women were exposed to tobacco
smoke chemicals at some point or another.

While second- and thirdhand smoke can cause negative health consequences in all exposed
people, the link between these chemicals and a woman’s reproductive health could serve to unite
women to advocate for this cause. Let’s stand together for clean air.

Click here to read the research study