Transition into menopause can last for several years

DEAR DOCTOR K: I am in my early 40s. Over the past several months, my periods have become less regular. Sometimes my flow is lighter than normal; other times it’s heavier. Is this perimenopause?

DEAR READER: It could be, though you’re a bit young. As a woman approaches menopause, periods often become irregular.

A woman is said to be in menopause after she has gone for one full year without periods.

The transition into menopause is called perimenopause. This phase begins when a woman notices changes in her cycle, usually in her mid-40s. It ends with menopause. Perimenopause usually lasts three to five years — but it can take as few as two years or as many as eight years for some women.

A woman’s ovaries produce eggs and the female hormones estrogen and progesterone. These hormones control a woman’s periods and other processes in her body. As a woman approaches menopause, her ovaries make less and less of these hormones.

As hormone levels fall, a woman’s pattern of menstrual bleeding usually becomes irregular. A woman can have irregular periods for several months to years before her periods finally stop. Many women experience light, skipped or late periods during perimenopause. However, there also can be heavier and more prolonged bleeding during perimenopause. This may be caused by progesterone levels that drop faster than estrogen levels.

Another common symptom of perimenopause is hot flashes. A hot flash is a feeling of suddenly being hot, flushed and uncomfortable. Hot flashes come in bursts or flushes that usually last a few seconds to a few minutes. They are caused by changes in the way blood vessels relax and contract, and are thought to be related to the changes in a woman’s estrogen levels. They may also be related to brain hormone levels that act on a woman’s ovaries to affect their production of estrogen.

As estrogen levels fall, the vagina’s natural lubricants also decrease. In some women, this causes vaginal dryness. The lining of the vagina gradually becomes thinner and less able to stretch. These changes can cause sex to be uncomfortable or painful. They can also lead to inflammation in the vagina.

Depression also may occur at a higher rate in perimenopausal women than in premenopausal women. And women with a history of depression are prone to flareups during perimenopause. (But non-hormonal events such as career challenges and children leaving home may affect depression as much or more than hormone changes.) Weight gain is also common around perimenopause.

Some of the symptoms and complications of perimenopause improve with time — particularly the irregular bleeding. Other symptoms persist into menopause, including hot flashes, vaginal dryness and depression.

We’ve discussed in this space before that the belief that menopausal symptoms tend to last no more than five to 10 years may be wrong. In some women, the symptoms may last much longer.

There are some simple blood tests that your doctor can perform to determine if you are entering perimenopause. I’d suggest you discuss that possibility with your doctor.