For most women, menopause occurs naturally around age 51. However, there are several reasons why menopause sometimes happens early or prematurely. For women who experience menopause before age 40, this is called premature menopause. For women who experience menopause between the ages of 40 and 45, this is called early menopause. About 1% of women under 40 experience premature menopause, while 5% of women under 45 experience early menopause. Hysterectomies, hypothyroidism, and cancer can all lead to early or premature menopause. Here’s how and why this occurs.
Early Menopause Due to Hysterectomy
As many as 600,000 women undergo hysterectomies in the US each year. A hysterectomy is a common procedure done to remove the uterus. They’re used to treat many conditions, such as excessive bleeding and fibrosis. In a Duke University study comparing the hormonal impact of women who had hysterectomies to those who had intact uteruses, researchers found that younger women who undergo hysterectomies have an increased risk of developing menopause early – almost two times more likely.
The study, which is the largest analysis of its kind, had almost 900 participants, with women from ages 30 to 47. While half of the women had no surgery, the other half underwent hysterectomies but still had at least one ovary. Preserving at least one ovary is meant to help women’s hormone production to continue as normal, yet 14.8% of the women with hysterectomies experienced menopause. It is currently unknown what causes the ovaries of some women to shut down after they undergo a hysterectomy.
Early Menopause Due to Hypothyroidism
Studies show that some women experience premature ovarian failure as a result of hypothyroidism. Premature ovarian insufficiency (POI) is a medical term for menopause before the age of 40 with no obvious surgical or medical cause. This is very rare, as it’s estimated that between .3 and 1% of women experience POI.
For women that do experience POI, 10 to 30% already have an autoimmune disorder. The most common in these cases is hypothyroidism. This is known to occur in women as young as 33. Hypothyroidism can also result in intermittent ovarian failure, meaning some women experience periods of amenorrhea (lack of period) and irregular periods.
Early Menopause Due to Cancer
Cancer treatment can have a lot of negative side effects. For women who get breast, ovarian, or uterine cancer, premature menopause may occur. Cancer treatment varies, but if the removal of the ovaries is required, premature menopause will follow. Additionally, chemotherapy and radiation can result in premature menopause.
Apart from the causes above, there are several more factors that can contribute to premature menopause. Smoking, family history, chromosomal abnormalities, and certain infections, like mumps, can also play a role. Symptoms of premature menopause typically include standard menopause symptoms, such as hot flashes, urinary urgency, night sweats, cold flashes, vaginal dryness, emotional changes, headaches, and more.
Talk to your doctor if you think you may be experiencing premature or early menopause. In most cases, hormone replacement therapy is recommended, which will provide menopause relief as well as some protection against the risks of premature menopause. With proper care and management, women in premature menopause go on to live normal, happy lives.