The mean duration of the climacteric phenomena, from the commencement of these until the final cessation of menstruation, is about two years. This mean is made up of extremely wide individual variations; in a small proportion of the cases the climacteric manifestations may last no more than a month or two, whilst at the other end of the scale we meet with cases in which the duration extends to 4, 6, 8, and even 18 years.
In considerably more than half of all the cases, however, the duration of the climacteric manifestations varies between six months and three years. Thus, in Tilt’s series of cases, the duration of the “change of life” was
| 6 months in | 12.07 of all cases |
| 1 year in | 22.64 of all cases |
| 2 years in | 18.62 of all cases |
| 3 years in | 9.43 of all cases |
6. Premature, Delayed and Sudden Onset of the Menopause.
In exceptional cases, the menopause, instead of taking place between the fortieth and the fiftieth year of life, occurs at an abnormally early or an abnormally late age.
Premature cessation of menstrual activity, in the third or the fourth decennium of life—very rarely indeed before the third decade—depends in part upon disturbances of metabolism and of haematopoiesis, and in part upon diseases of the female reproductive organs; in some cases, however, it may be due to some hereditary constitutional peculiarity; or it may occur suddenly, in consequence of some violent shock to the nervous system.
Among the disorders of metabolism which may lead to a premature menopause, excessive adiposity, lipomatosis universalis, occupies the first place. Next in order of importance come a chloro-anæmic condition of the blood, pernicious anæmia, splenic leukaemia, certain of the acute infectious disorders—typhoid, cholera, scarlatina, acute articular rheumatism,—further pulmonary tuberculosis, diabetes mellitus, Graves’ disease, Addison’s disease, and myxoedema. These various conditions may give rise, in part by infective processes, and in part in consequence of the general cachectic condition, to atrophy of the ovaries with destruction of the graafian follicles, and to atrophic processes in the uterus, and these changes lead to the premature cessation of menstrual activity.
Excessive obesity has a restrictive influence upon ovarian activity, manifested in part, as already mentioned, by the occurrence of sterility, but in part also, in very obese women, by the onset of a premature menopause. Among 215 cases of extreme obesity in women, I found 49 in which the menopause occurred at a remarkably early age. In these cases the menopause occurred at the following age:
| In | 1 woman at the age of | 17 years |
| In | 14 women at the age of | 20 to 25 years |
| In | 11 women at the age of | 25 to 30 years |
| In | 9 women at the age of | 30 to 35 years |
| In | 14 women at the age of | 35 to 40 years |
In none of these cases did the local examination of the reproductive organs disclose the existence of any noteworthy disease.