How long does GnRH analogue therapy take to work for an ovarian endometrioma?

GnRH analogues suppress ovarian hormone activity, which may reduce endometriosis-related inflammation, pelvic pain, or bleeding. Symptom relief and a change in the endometrioma are not the same outcome: pain may improve without the cyst disappearing, and imaging may be needed to see whether its size or appearance has changed. The medicine may also cause hot flushes, vaginal dryness, mood changes, or other low-oestrogen effects. Your gynaecologist decides how long treatment is suitable and whether another approach is needed.

Keep appointments and record pain, periods, bloating, pain with sex, and any medication effects. Use the prescribed schedule and do not delay a review because symptoms fluctuate. Ask when an examination or scan is planned and what result would change management. Discuss add-back hormones, bone protection, fertility plans, and whether surgery or observation has a place in your care. You can read about the condition in [Ovarian Endometrioma](/conditions/ovarian-endometrioma/) and the medicine in [GnRH Analogue Therapy](/treatments/medical-gynaecology/gnrh-analogue-therapy/).

Contact your gynaecology team for persistent or worsening pain, new pressure symptoms, troublesome bleeding, or side effects affecting your wellbeing. Seek urgent care for sudden severe one-sided pelvic pain, fainting, persistent vomiting, fever with pelvic pain, or heavy bleeding with dizziness. Those symptoms need assessment rather than waiting for the next planned scan or dose.

Ask how the endometrioma will be monitored, when symptom improvement should be reviewed, whether treatment is intended to shrink it or control symptoms, and how the plan fits with pregnancy intentions.