What causes menopause?

There can be multiple factors that can result in menopause. They are:

1. Natural decline of hormones:

n the late 30s, ovaries start making less of the hormones that control the menstrual period, making it harder to get pregnant. These are called estrogen and progesterone.

In the 40s, the menstrual periods may get longer or shorter, heavier or lighter, and happen more often or less often. In time, the ovaries stop releasing eggs, which means then there are no more periods. This happens on average around age 51.

2. Oophorectomy (surgery to remove ovaries).

Ovaries make hormones, including estrogen and progesterone, that control the menstrual cycle. Surgery to remove the ovaries causes instant menopause. Your periods stop. You’re likely to have hot flashes and other menopausal symptoms. Symptoms can be severe because the surgery causes hormones to drop all at once rather than slowly over several years.

3. Chemotherapy and radiation therapy

These cancer therapies can cause menopause. They can cause symptoms such as hot flashes during or shortly after treatment. Periods sometimes return after chemotherapy, in which case you can still get pregnant.
Radiation therapy aimed at the pelvis, belly and lower spine can cause menopause. Radiation to the whole body for stem cell transplant also can cause menopause. Radiation therapy to other parts of the body, such as breast tissue or the head and neck, likely won’t affect menopause.

4. Primary ovarian insufficiency

About 1% of people who have menopause get it before age 40. This is called premature menopause. Premature menopause may result from the ovaries not making the usual levels of hormones. This is called primary ovarian insufficiency. It can happen from gene changes or an autoimmune disease.
Often no cause of premature menopause can be found.