When to worry about a missed period with hypothalamic amenorrhoea

Hypothalamic amenorrhoea can occur when the brain reduces the signals that coordinate ovulation and menstrual cycles. This may be associated with low energy availability, intense exercise, emotional strain, weight change or illness. Pregnancy can still occur if ovulation happens unexpectedly, so a pregnancy test may be relevant even when periods have stopped.

The condition can affect oestrogen levels. Without appropriate review, low oestrogen may affect vaginal comfort, fertility planning and bone health. A clinician may ask about food intake, exercise, stress, medicines and changes in weight before deciding which examinations or tests are useful.

Arrange a non-urgent appointment if your periods have stopped or become widely spaced, especially if this is a change from your usual pattern. Record the date of your last bleed, any spotting, exercise changes, recent illness, eating difficulties and medicines. Avoid increasing training or restricting food while waiting for advice; restoring adequate nourishment and reducing excessive strain may be part of care.

Seek urgent medical care for severe pelvic pain, fainting, heavy bleeding, a positive pregnancy test with pain or bleeding, chest pain, severe weakness, confusion or inability to keep fluids down. Contact a clinician soon for new vision changes, persistent headaches, milky nipple discharge, marked dizziness or symptoms of an eating disorder. These features need assessment rather than being attributed to hypothalamic amenorrhoea alone.

Ask whether pregnancy testing, hormone testing, nutrition support or a bone-health assessment is appropriate. You can also ask how to adjust exercise safely, what menstrual changes to track, and when a follow-up appointment should occur.