Many women worry about the risks of cancer related to oral contraceptives. Few women appreciate that oral contraceptives actually decrease the risk of some cancers in women.
A study published last week in the journal, JAMA Oncology, looked at almost 200,00 women ages 50-71. The study compared those who took oral contraceptives during their reproductive years vs. those who had not.
The study demonstrated that women who had used oral contraceptives for more than 10 years had a 34% decrease in their incidence of endometrial cancer. Women who smoked and were obese, whose risk was greatest, saw the most benefit. Oral contraceptive users had a 40% reduced risk of ovarian cancer, with decreased risk in smokers, the obese, and those who rarely exercised (women in a higher risk category). These results are highly significant.
Additional data did not demonstrate an increase in breath cancer in previous users of oral contraceptives. Colorectal cancer risk was also not increased.
The NIH-AARP Diet and Health Study was prospective and began in 1995 and continued to 2011. The study included at least 100,000 previous users of birth control pills. The decrease in ovarian cancer was similar along modifiable lifestyle factors, and the decrease continued with the duration of use. Similarly, the decrease in uterine cancer strengthened with duration of use.
Physicians believe that these benefits are derived from the changes in uterine and ovarian function in oral contraceptive users. Oral contraceptives provide a level of progesterone that decreases proliferation or growth of the endometrial lining, which is why menstrual bleeding is so much less on the pill . Endometrial cancer is caused by increased growth in the lining of the uterus.
Epithelial ovarian cancer develops from the surface of the ovary. The surface is disrupted each month during ovulation. Oral contraceptives inhibit ovulation and therefore a disruption of the epithelial surface of the ovary. Women who have had pregnancies (lack of ovulation for at least 9 months each time) have fewer ovarian cancers than women who have never conceived.
How does this information apply to women in their later reproductive years? Use of oral contraceptives will provide excellent birth control and regulate menstrual cycles which often become irregular and heavier in the peri-menopausal years. Oral contraceptives can regulate hormone levels during the years when there are more swings in levels which can affect mood, headaches, PMS, etc. In most peri-menopausal women, oral contraceptives can be used until the average age of menopause, age 52, if there are no contraindications such as hypertension, blood clots, and heart disease. Your gynecologist can determine if this is a good option for you.
Marilyn C. Jerome, MD
Foxhall OB-Gyn Associates
New York Times. January 19, 2018. Oral Contraceptives Reduce Risk for Ovarian and Endometrial Cancers
JAMA Oncology. Modification of the Association Between Duration of Oral Contraceptive Use and Ovarian, Endometrial, Breast and Colorectal Cancers. January 18, 2018, by Kara Michels, PhD
Gynecologists treat “genitourinary syndrome of menopause” with many modalities, but a common treatment is vaginal estrogen. Many women are concerned about the risks of estrogen, and there are very significant differences in the absorption of topical vaginal estrogen and systemic hormones, taken orally or topically as a patch or gel.
First, let’s define genitourinary syndrome of menopause. The lack of estrogen in the vaginal wall and vulvar tissues causes thinning of the tissue and decreased blood supply. The symptoms include vaginal dryness, burning, irritation, decreased lubrication, painful intercourse, and urinary symptoms of urgency, frequency, painful urination, incontinence and increased urinary tract infections. Quality of life can be adversely affected. The frequency of these symptoms is reported in 20-45% of postmenopausal women, but actually most women experience at least one of these symptoms.
Vaginal estrogen products are provided in creams, vaginal pills, and and a silicone ring that is left in place for three months. Although the serum level of estrogen rises when these products are first administered, the maintenance dose results in a serum estrogen level that remains in the postmenopausal range. The question is whether these products are related to in increase in blood clots, heart attacks, strokes, and breast cancer.
The significant symptoms of genitourinary syndrome and the need for long-term use of vaginal estrogen makes it critical that studies be done to demonstrate safety. A study in Menopause: The Journal of the American Menopause Society, published in January, 2018, analyzed data from the Women’s Health Initiative. The use of vaginal estrogen was evaluated through self-assessment questionnaires, but type of vaginal estrogen was not stratified. The average age of patients in the study was 65 years, and mean follow-up was 6-7 years, with an average time using the products was about 40%.
The study results demonstrated that postmenopausal women who took vaginal estrogen had similar risks of breast cancer, stroke, colon cancer, endometrial cancer, blood clots and pulmonary emboli as those who had not used vaginal estrogen. The study actually demonstrated decreased risks of hip fracture and coronary artery disease.
Breast cancer patients on aromatase inhibitors will exhibit an increased serum estrogen level than the reduced level of estrogen derived from use of these medications, and probably should not use vaginal estrogen products. Women who have or have had breast cancer may be able to use vaginal estrogen if approved by their oncologist on a case by case basis.
If you read the package insert of vaginal estrogen products, the labeling is the same as higher dose systemic products. The American Menopause Society is advocating for a change in the labeling because this study and almost every other observational study done thus far do not demonstrate an increased risk for vaginal estrogen users. Currently the FDA is considering a proposal to change the warning label. Stay tuned!
Marilyn C. Jerome, MD
Foxhall OB-Gyn Associates
Menopause: The Journal of the American Menopause Society, Volume 25, Number 1, January 2018. Breast cancer, endometrial cancer, and cardiovascular events in participants who used vaginal estrogen in the Women’s Health Initiative Observational Study. Carolyn Crandall, MD, et al.