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Incidence and Risk Factors |
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The prevalence of spontaneous premature menopause is generally accepted as 1% of women aged less than 40 years and 0.1% for those less than 30 years (based on population studies of predominately Caucasian women). Early menopause affects approximately 5-10% women in the general population. However, there does appear to be some variation related to ethnicity and the population studied which may reflect real differences and/or study bias. The Study of Women Across the Nation (SWAN) reported a significantly lower prevalence of spontaneous premature ovarian failure (POF) in Asian women (0.5-0.1%) compared with Caucasian, African American or Hispanic women (1-1.4%) living in the USA. An 8% incidence of medically induced premature menopause was reported in a study of childhood cancer survivors.
Observational studies have identified a number of risk factors associated with spontaneous premature menopause (see Table: Risk factors associated with spontaneous early/premature menopause). The reported incidence of a positive family history in women with spontaneous premature menopause ranges from 4-50%. The mode of transmission appears to be variable with both X linked and autosomal inheritance proposed. The risk of premature menopause/early menopause for other females in the family increased 9-fold in the setting of an affected sister; 12-fold where multiple affected relatives and 8-fold where there was a family history of premature menopause. Poor response to ovarian stimulation, as reflected by a low number of retrieved oocytes at first IVF collection, is considered to be a predictor of an earlier menopause; occurring within ten years of the first treatment. The relationship between premature menopause and variables such as body mass index (BMI), parity, education level, previous breastfeeding or marital status remains unclear with conflicting reports in the literature.
| Table: Risk factors associated with spontaneous early / premature menopause |
| Risk factor |
Comment |
| Family history |
Risk increased up to 12-fold |
| Smoking |
Increased risk |
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Poor response to ovarian stimulation in assisted reproduction |
Increased risk |
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Epilepsy |
Increased risk |
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BMI
Earlier menarche
Irregular menstrual cycles / cycle length
Decreased parity/ nulliparity
Education level
Previous breast feeding
Marital status |
Conflicting reports in the literature regarding the significance of these variables as risk factor |
Content updated November 20, 2007
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Last Updated ( Monday, 10 December 2007 )
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