Menopause is defined as a woman not having her period for 12 months in the absence of another cause (e.g., nursing, birth control, eating disorders). This happens when ovaries stop producing large amounts of estrogen (and progesterone) and women no longer ovulate. Hormonal changes and symptoms usually begin before this happens, during a time called perimenopause.
Perimenopause (the time leading up to menopause) generally begins begins when a woman who had regular cycles (with a predictable length and flow) starts having irregular periods. Women enter perimenopause on average about 4 years before they stop having periods altogether. However, there is a broad range for the length of perimenopause. Some women may enter perimenopause up to 10 years before their last menstrual period and some women experience hot flashes/flushes even while they have regular periods. Menopause and perimenopause are normal transitional periods in a woman’s life, but they often cause very bothersome symptoms.
With the onset of perimenopause, fluctuations in hormone levels may cause irregular menstrual cycles, headaches, mood changes, insomnia, weight gain, breast pain (mastodynia), and hot flashes/flushes.
With the onset of menopause, a dramatic decrease in estradiol (the body’s primary estrogen) and progesterone causes more changes, including:
Hot flashes: This is the most common symptom of menopause and perimenopause affecting up to 80% of women. They typically last 5–7 years but can last up to 10–15 years.
Absence of menstrual cycles: This is the hallmark of menopause. Once women stop ovulating, their uterine linings no longer grow and shed.
Loss of bone density: Normally, bone remains strong by having a perfect balance between the cells that make bone (osteoblast) and cells that breakdown bone (osteoclast). Until menopause, estrogen protects bones from being broken down in excess by osteoclasts. When estrogen is lost and osteoclasts go unchecked, bone density is lost. This can result in osteoporosis leading to a higher risk of hip fractures, wrist fractures, and spine fractures, among others.
Weight gain and bloating: Estrogen helps regulate the deposit of fat tissue. Many women gain weight during and after the menopausal transition.
Mood changes: Mood changes, like depression, are common during perimenopause and menopause.
Sleep disturbances: Sleep disturbances can be related to the underlying hormonal changes or simply from night sweats.
Increased risk of cardiovascular disease.
Genital changes: These include vaginal shrinkage, thinning of the vaginal tissue, loss of vaginal folds, loss of vaginal lubrication, vaginal itching and discomfort, and painful sex (dyspareunia).
Urinary symptoms: Women can feel the sudden need to urinate (urgency), frequent urination, and pain on urination—mimicking a urinary tract infection.
Perimenopause and menopause can pose many challenges but certain conditions that are worsened by higher estrogen levels improve after menopause. These include endometriosis, uterine fibroids, adenomyosis, symptoms related to heavy, painful periods, and PMS.