Unpredictable endocrinology of the menopause transition: clinical, diagnostic and management implications.

The approach to menopause can be divided into the early (E) and late (L) menopausal transitions (MT) on the basis of menstrual irregularity (EMT) and subsequent observation of at least one episode of 60 or more days amenorrhoea (LMT). In total, 40-60% of cycles in the LMT are anovulatory, often with low oestradiol (E2) and high follicle-stimulating hormone concentrations. The ovulatory cycles have variable endocrine characteristics, none of which is specific to EMT or LMT. Hormonal measurements of FSH and E2 are thus of little diagnostic value because of their unpredictable variability. Symptoms during the transitions may result from high or low E2 and can often be satisfactorily managed with low-dose oral contraceptives, which suppress pituitary-ovarian function.