The International Menopause Society (IMS) and the World Health Organization (WHO), with the aim of standardizing the terminology of menopause have put forward the following definitions:
- Perimenopause – the period immediately prior to the menopause (when the endocrinological, biological, and clinical features of approaching menopause commence) and the first year after menopause
- Menopausal transition – the period of time before the final menstrual period (FMP) when variability in the menstrual cycle is usually increased. This term can be used synonymously with "premenopause" although this latter term can be confusing and preferably should be abandoned
- Climacteric – the phase in the aging of women marking the transition from the reproductive phase to the non-reproductive state. This phase incorporates the perimenopause by extending for a longer variable period before and after the perimenopause.
- Climacteric syndrome – the climacteric is sometimes, but not necessarily always, associated with symptomatology. When this occurs, it may be termed the "climacteric syndrome."
- Premenopause – the term premenopause is often used ambiguously to refer to the one or two years immediately before the menopause or to refer to the whole of the reproductive period prior to the menopause. The group recommended that the term be used consistently in the latter sense to encompass the entire reproductive period up to the FMP
- Postmenopause – the term postmenopause is defined as dating from the FMP, regardless of whether the menopause was induced or spontaneous
- Premature menopause – ideally, premature menopause should be defined as menopause that occurs at an age less than two standard deviations below the mean established for the reference population. In practice, in the absence of reliable estimates of the distribution of age at natural menopause in populations in developing countries, the age of 40 years is frequently used as an arbitrary cut-off point, below which menopause is said to be premature
- Induced menopause – the term induced menopause is defined as the cessation of menstruation which follows either surgical removal of both ovaries (with or without hysterectomy) or iatrogenic ablation of ovarian function (e.g. by chemotherapy or radiation)
Last reviewed 02/2020