Adenomyosis (ad-uh-no-my-O-sis) occurs when endometrial tissue, which normally lines the uterus, exists within and grows into the muscular wall of the uterus. This happens most often late in your childbearing years after having children.

Adenomyosis differs from endometriosis — a condition in which the uterine lining becomes implanted outside the uterus — although women with adenomyosis often also have endometriosis. The cause of adenomyosis remains unknown, but the disease typically disappears after menopause. For women who experience severe discomfort from adenomyosis, certain treatments can help, but hysterectomy is the only cure.

Symptoms Causes Risk factors Complications

Sometimes, adenomyosis is silent — causing no signs or symptoms — or only mildly uncomfortable. In other cases, adenomyosis may cause:

  • Heavy or prolonged menstrual bleeding
  • Severe cramping or sharp, knife-like pelvic pain during menstruation (dysmenorrhea)
  • Menstrual cramps that last throughout your period and worsen as you get older
  • Pain during intercourse
  • Bleeding between periods
  • Passing blood clots during your period

Your uterus may double or triple in size. Although you might not know if your uterus is enlarged, you may notice that your lower abdomen seems bigger or feels tender.

When to see a doctor

If you experience any signs or symptoms of adenomyosis, such as prolonged, heavy bleeding during your periods or severe cramping, and they interfere with regular activities, make an appointment to see your doctor.

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