Menopause is considered premature if it occurs due to ovarian failure, or as a result of ovarian removal or damage before the age of 40. Premature natural menopause can be the result of genetics, illness, or autoimmunity.

Premature menopause and premature ovarian failure are not, however, always one and the same.  Menopause is the very last menstrual period, which can only be as a result of permanent ovarian failure.  Not all cases of premature ovarian failure are permanent, and in some cases periods return. 

There are several features which play a part in governing when the menopause will occur, but only 2 have so far been identified as contributory factors: Genetics and Smoking. 

Genetic factors

Familial / genetic factors are known to influence the age of onset of perimenopause.  Many women will experience it at a similar age to their mothers and sisters.  The risk of surgical menopause is also contributed to by genetic factors. 

Smoking

Current smoking habits have been identified as a cause of early menopause, usually inducing a shift of approximately 1.5 years.  The degree of change in the time of onset of perimenopause is directly related to the number of cigarettes smoked and the time spent as a smoker. 

Pregnancy

Another factor that could cause early or late menopause is a woman's pregnancy history.  It is thought that multiparity (having a history of more than one pregnancy) may lead to a later menopause.  Nulliparity (history of no pregnancy) may contribute to the risk of earlier menopause. 

Hysterectomy

In the case of a hysterectomy, removal of ovaries will result in an immediate menopause.  When they are not removed during the procedure, there is a 50% chance of experiencing menopause within the following 5 years.

Diabetes

Menopause occurs before the age of 47 in women with type 1 diabetes.  Diabetic females also experience an earlier menarche (onset of menstrual periods) than non-diabetics, thus the number of reproductive years for diabetic females is on average 30, compared to 35-37 for non-diabetic women. 

Stress

Although there is little or no evidence to suggest that stress or depression can be risk factors for early menopause, they have been shown positively to influence the severity of symptoms experienced during perimenopause, making stress management an important part of coping with the transition.  

Other factors

Other factors include a high body-mass index, which is thought to lead to late menopause, and medically treated depression or toxic chemical exposure, which are thought to contribute to earlier menopause. 

No links have been found between the age of menopause and the taking of oral contraceptives, marital status, socio-economic status, race, or age of menarche (onset of periods). 

20/05/2009