Women’s Risk for Lung Cancer Linked to Reproductive History

Lung cancer is the second most common occurring cancer and leading cause of cancer death in both men and women. And while most women are more concerned about breast cancer, lung cancer kills more women than breast, cervical and ovarian cancers combined.

Decades ago, lung cancer was considered a man’s disease. But new lung cancer rates among women rose 84 percent over the past four decades, compared to men’s rates which dropped by 36 percent, according to the American Lung Association.

“Most non-smoking women don’t consider themselves at risk for lung cancer,” says Bernard Kaminetsky, MD, medical director, MDVIP. “However, the truth is, all women are at risk, even non-smokers.”

Smoking is the leading risk factor for lung cancer, but it’s only responsible for 85 percent of cases. Additional contributors include genetics, exposure to carcinogens like secondhand smoke, asbestos and radon and use of supplements for beta-carotene (precursor to vitamin A) and vitamin E. There’s also a growing body of evidence that suggests estrogen may play a role in the development of lung cancer.

Estrogen is a category of hormones responsible for the development and regulation of reproductive system. For years, it’s been linked to breast, ovarian and endometrial (uterine) cancers. Lung cancer scientists turned their attention to estrogen a few years ago and have found that non-small cell lung cancer, particularly adenocarcinoma, is an estrogen receptor positive cancer.

Another piece of the puzzle may have been found. Researchers from Second Xiangya Hospital, Central South University (Changsha, China) began studying how reproductive years affect the risk for lung cancer. They found that going through menopause early, beginning menstruation early, giving birth to your first child at a younger age and having a shorter reproductive life span were associated with a higher risk for lung cancer, according to a study presented at the International Association for the Study of Lung Cancer 2023 World Conference.

In this study, researchers conducted a prospective cohort study using 273,190 participants from the UK Biobank. Their goal was to identify potential risk factors and see how they affect specific variables such as:

• Women’s age
• Smoking status 
• Body mass index 
• Genetic risk 
• Histological subtypes (growth patterns of tumors)
• Women’s age at first period
• Women’s menopausal age
• Reproductive life span
• Women’s age at first live birth
• Number of live births, stillbirths, miscarriages and abortions
• History of hysterectomy and or oophorectomy
• History of oral contraceptives and/or hormone replacement therapy

Researchers did not factor in exposures to harmful environmental chemicals into the analysis.

After an average follow-up period of 12 years, researchers documented 1,182 cases of lung cancer in women. After analyzing data for relative risk (the probability of something occurring in one group compared to another), researchers found the following variables significantly raised the risk for lung cancer among women:

• Menstrual cycle beginning at age 11 or younger. 
• Menopause at age 46 or younger.
• Reproductive years spanning 32 years or less had a 42 percent higher risk; however, if it spanned 33 to 35 years, the risk was 24 percent higher.
• First birth at age 20 or younger had a 63 percent higher risk, while women with first birth between 21 and 25 had a 31 percent higher risk.

“Obviously, you can’t control many of these risk factors,” says Kaminetsky. “However, there are many lifestyle behaviors you can adopt that can help lower your risk.”

4 Tips to Help lower Your Risk for Lung Cancer

Avoid tobacco. Tobacco use — including cigarettes, cigars, pipes and chewing tobacco —is the biggest risk factor for most lung cancers. If you smoke, skip beta-carotene supplements, as it can raise your risk for lung cancer. You also should talk to your doctor. They may be able to help refer a smoking cessation program to you or prescribe nicotine replacement therapies.

Eat plenty of fruits and vegetables. Produce is a good source of phytochemicals, which studies have found to help lower the risk of cancer, including lung cancer. The American Lung Association recommends eating berries, dark-green vegetables, oats and fish. Your doctor can help make dietary recommendations or refer you to a dietician.

Exercise regularly. Exercise helps strengthen respiratory muscles and endurance; however, experts don’t feel it can reverse lung damage. Overall, studies have found that regular exercise, which includes weightlifting and aerobic training can help lower the risk of lung cancer. Make sure you consult your physician before beginning or changing an exercise program.

Protect yourself from environmental exposures. Get your home tested for radon. Dodge secondhand smoke as much as possible. And take steps to avoid third-hand smoke.

If you don’t have a physician, consider joining an MDVIP-affiliated practice. MDVIP-affiliated have the time to work with you to focus on your health and wellness. Find a physician near you and begin your partnership in health »