Amenorrhoea

Amenorrhoea is the absence of menstrual periods — either periods that never started (primary) or periods that stop for three months or more having previously been present (secondary), outside pregnancy and breastfeeding. Causes include pregnancy, PCOS, thyroid problems, high prolactin, very low body weight or heavy training, premature ovarian insufficiency and, occasionally, scarring inside the womb. Persistent absence of periods should always be assessed.

Also known as: amenorrhea, no periods, periods stopped

Last reviewed: 8 September 2026. Written by the Antega Editorial Team. General information only — always follow the advice of your own clinic, doctor or pharmacist.