Does taking hormone supplements for menopausal symptoms increase ovarian cancer risk?

Menopause is cessation of menstruation and the ability to conceive and give birth. Although sometimes called “the change of life”, that definition has negative connotations and is inappropriate. Physical, mental and sexual changes occur, but they cannot be called deterioration.

• What is menopause? Symptoms, effects and management strategies

The term entered Turkish from French ménopause, combining meno and pause. Meno comes from Greek men (month) and pause (stopping, cessation) combined together.

The ovaries have a natural lifespan of approximately 35 years. As their function declines, estrogen and progesterone production falls and menopause, the postmenopausal period, begins. Hormonal deficiency, especially estrogen, causes anxiety, hot flushes, depression, memory problems and other distressing conditions. Hormone replacement therapy (HRT) has been used since the 1960s to relieve these. Prescriptions have increased dramatically in recent years. Estrogen was initially given alone, but associated risks led to adding progesterone.

HRT was known to somewhat increase heart disease and breast cancer risk; recent studies also identified increased endometrial cancer risk.

Trabert and colleagues’ study published in February 2013 found that among postmenopausal HRT users, 68,000 women, 885 developed endometrial cancer. Estrogen-added progesterones used for 10 years or longer, for 15 days or fewer monthly, significantly increased risk compared with no HRT. Risk was also emphasized in women who were not overweight or obese.

A newer study found increased ovarian cancer risk too. Researchers estimated that among HRT starters in their 50s, every 1000 women might include 1 ovarian cancer case, with ovarian cancer causing one death per 1700 women.

For a study published in February 2015 in Lancet, postmenopausal women with ovarian cancer, 21,488 in total, were assessed for many risk factors. HRT significantly increased ovarian cancer risk, highest during current use and remaining higher than nonusers for 5 years after stopping. Estrogen alone and estrogen–progesterone combinations carried similar risk.

America and England currently have 6 million known HRT users. WHO, EU and United States guidance does not mention ovarian cancer risk, while England highlights possible risk with prolonged use. This study provides strong evidence of increased risk. Particularly considering highest risk around starting age 50, guidance should be reviewed, patients better informed and HRT used only with physician advice and prescription.

Keywords: menopause, cancer risk, ovarian cancer, HRT, hormone replacement therapy, estrogen, progesterone, postmenopause