Premature Menopause: Causes
Premature ovarian insufficiency (POI) can be primary, when periods never start due to the ovaries being absent, poorly developed, or unable to function; or secondary when ovarian function has occurred and a period pattern has been established but then ovarian function and hence periods stop early.
Causes of POI include
| Primary POI | Secondary POI |
| Chromosome abnormalities | Chemotherapy and radiotherapy |
| Enzyme deficiencies | Removal of ovaries |
| Autoimmune disease | Infection- TB and mumps |
| Autoimmune |
Premature or early menopause may follow surgery such as hysterectomy when the ovaries may be removed along with the womb, or may occur early even if the ovaries are left in place at the time of hysterectomy.
Other causes of early or premature menopause include chromosomal disorders such as Turner's syndrome and Down's syndrome, autoimmune disorder (when antibodies which work against the ovaries are produced), and chemotherapy or radiotherapy. Some drugs may stop the ovaries functioning early but usually ovarian function resumes when the drug is stopped.
For many women with POI, especially secondary POI, no particular cause is found, but there may be a family history of POI, suggesting a genetic influence either on the number of egg cells present in the ovaries, or on the rate at which egg cells are lost.