Overview
Identify ovarian and central oestrogen deficiency early, establish the cause and fertility implications, and provide physiological sex-steroid replacement that protects bone, cardiovascular and genitourinary health.
Ovarian hypogonadism follows follicle depletion or dysfunction from genetic conditions, autoimmune disease, surgery, chemotherapy, radiotherapy or an unexplained process. Gonadotrophins rise because ovarian negative feedback is lost. Central hypogonadism follows deficient hypothalamic GnRH or pituitary LH and FSH, as in relative energy deficiency, pituitary lesions, hyperprolactinaemia, chronic disease or opioid exposure. These mechanisms lead to different investigations and fertility treatments.
Loss of oestradiol can cause hot flushes, sleep disruption, vaginal dryness, sexual pain, low libido and mood symptoms, but absence of symptoms does not protect bone. Prolonged deficiency before the expected menopause is associated with low bone density and adverse cardiometabolic effects. Replacement in POI is physiological restoration for a young deficient person, not the same risk-benefit question as initiating HRT decades after natural menopause.