What causes perimenopause?

Perimenopause is caused by the natural aging process. As a woman gets older, her body gradually produces less of the hormones estrogen and progesterone, although it can fluctuate quite a lot. In turn, this causes changes in the body that lead to the complete end of menstruation, or menopause. The follicles that release eggs are diminished, and respond less reliably to FSH (follicle-stimulating hormone). This process usually begins when a woman reaches her early 40s and ends in her early 50s. The average woman in the United States reaches menopause at around age 51.

Patricia Geraghty, NP
Women's Health

Perimenopause begins when the aging follicles, the immature eggs that are in the ovaries since before a woman is born, begin to respond less reliably to the hormonal messages from the brain. FSH from the pituitary stimulates the final development of follicles. When the follicles are older, this development is irratic, leading to fluctuating ovarian hormone levels before hormones levels eventually begin to drop.

Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)

Perimenopause or pre-menopause occurs as the levels of estrogen begin to decline in a woman's body. Women may experience unpleasant symptoms as estrogen levels begin to decline because this hormone affects every area of the body including the brain, blood vessels, bone, skin, heart, uterus, lungs, intestines and breasts. If estrogen doesn't get to these cells, physiological changes occur. That is what causes menopausal symptoms, from hot flashes and night sweats to bone loss and vaginal tissue thinning and dryness. Your monthly menstrual cycle will also become more erratic during this time. Talk to your doctor about how you might minimize the symptoms and discomfort of perimenopause.

The typical symptoms of perimenopause are when a woman's periods become less predictable before eventually stopping at full menopause. This lack of predictability is from her brain’s response to the aging of the remaining eggs in her ovaries. To have a period and ovulate (pass an egg), a woman’s brain must send stimulating hormones to her ovaries. With ovulation, the ovary makes estrogen and progesterone, but as the ovaries age, the brain has to issue increasingly higher levels of its stimulating hormones, with the ovary not always responding.

Continue Learning about Menopause

6 Things You Need to Know About Hormone Therapy
6 Things You Need to Know About Hormone Therapy
If you’re going through menopause or perimenopause, you may be experiencing symptoms such as hot flashes, sleep problems, vaginal dryness, or changes ...
Read More
What medications can help me manage perimenopausal rage?
Dr. Mehmet Oz, MDDr. Mehmet Oz, MD
For some women, the hormonal fluctuations that occur during perimenopause can trigger a condition ca...
More Answers
8 Signs and Symptoms of Menopause
8 Signs and Symptoms of Menopause8 Signs and Symptoms of Menopause8 Signs and Symptoms of Menopause8 Signs and Symptoms of Menopause
Cut Back on Caffeine to Cool Off Night Sweats
Cut Back on Caffeine to Cool Off Night Sweats

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.