• Clinical science



Menopause is the time at which a woman permanently stops menstruating, usually between 45 and 55 years of age, and is diagnosed after 12 months of amenorrhea. It is preceded by the climacteric period, sometimes referred to as perimenopause or menopausal transition, which is the transition period in a woman's life from the time of full sexual maturity to the onset of menopause. The physical manifestations are caused by hormonal changes (primarily a drop in progesterone and estrogen levels) that occur during the climacteric period. Clinical features leading up to menopause include irregular menses, autonomic symptoms (e.g., hot flashes), mental symptoms (e.g., mood swings), and atrophic features (e.g., reduced breast size, vaginal atrophy). Menopausal transition is a natural phase of the aging process in females, and as such does not usually warrant treatment. However, treatment is warranted in the case of severe symptoms or early onset menopause. The choice of treatment is decided on a case-by-case basis and includes conservative methods, hormone replacement therapy, and non-hormonal therapy.

Menopause occurring before the age of 40 is considered premature. A common cause of premature menopause is ovarian insufficiency. The diagnosis is confirmed by increased FSH levels occurring after more than three months of amenorrhea in a woman under the age of 40. Treatment involves hormone replacement therapy.


Perimenopause (menopausal transition, MT): The time period from the first instance of climacteric symptoms caused by fluctuating hormonal levels to one year after menopause: . (The duration can vary greatly in different women. However, the average length of perimenopause is 4 years.)

  1. Premenopause
    • The time period from the first occurrence of climacteric irregular menstruation cycles to the last menstrual period
    • Onset: usually 45–55 years of age
    • Characterized by increasingly infrequent menstruation
  2. Menopause
    • Time at which menstruation ceases permanently
    • Confirmed after 12 months of amenorrhea
    • The average age at menopause is ∼ 49–52 years.
  3. Postmenopause: : the time period beginning 12 months after the last menstrual period



↓ Ovarian function estrogen and progesterone levels → loss of negative feedback to the gonadotropic hormonesGnRH levels↑ levels of FSH and LH in blood (hypergonadotropic hypogonadism) → anovulatory cycles become more and more frequent → progressive follicular depletion → ovarian function eventually stops permanently

In menopausal women, estrogens are mainly produced by peripheral aromatase conversion of adrenal androgens in adipose tissue. Therefore onset of menopause might be delayed and symptoms might be milder in obese women.


Clinical features

The onset and intensity of symptoms is dependent on the phase of menopausal transition.

The onset and duration of these symptoms is widely variable. Symptoms may begin up to 6 years before the menopause and continue for a number of years after the last menstrual period!


Subtypes and variants



Diagnosis is usually clinical. However, certain laboratory tests may help confirm the onset/presence of perimenopause.

All postmenopausal women above the age of 65 should be screened for osteoporosis (i.e., using the DEXA scan to measure bone mineral density).

Hyperthyroidism and menopause present similarly. For this reason, serum TSH should be checked in all suspected perimenopausal cases with heat intolerance and disturbed sleep to determine the cause!




  • Treatment is not warranted for all women approaching or undergoing menopause, as it is a normal aging process. Treatment may be considered in the following cases:

Lifestyle modifications and local medical therapy

  • For hot flashes: avoidance of triggers (e.g., bright lights, predictable emotional triggers); environmental temperature regulation (e.g., using fans)
  • For atrophic vaginal symptoms: vaginal estrogen creams, rings, or tablets (estrogen therapy may reduce the incidence of UTIs and features of overactive bladder)
  • For impaired sleep and/or hot flashes: exercise, acupuncture, and relaxation techniques
  • Prevention of osteoporosis
    • Smoking cessation, adequate vitamin D intake and regular weight-bearing exercise
    • For more details, see “treatment” of osteoporosis.

Hormone replacement therapy (HRT)

HRT is usually employed for the short-term treatment of menopausal symptoms.

Non-hormonal therapy

Non-hormonal therapy is used to treat menopausal vasomotor symptoms in women who do not want to use hormonal medications or who have contraindications for HRT.


Disorders related with cessation of menstruation

Premature menopause (menopause precox)

  • Definition: : cessation of periods before the age of 40
  • Etiology

Early menopause is often associated with smoking!

Ovarian insufficiency