The cause of endometriosis is not known. It may be due to:

  • Menstrual tissue that backs up through the fallopian tubes and spills into the belly
  • An immune system that does not stop tissue from implanting on other organs
  • A lymph system that carries cells from the uterus
  • Surgery that accidentally relocates cells

Risk Factors

Endometriosis is more common in women of reproductive age. Other things that may raise the risk are:

  • Menstruating before the age of 10 years old
  • Having a cycle of less than 28 days
  • Having a flow of more than 5 to 6 days
  • Having an abnormal reproductive tract
  • Not having children



Some people do not have problems from endometriosis. Others may have mild to severe problems, such as:

  • Cramping and pelvic pain before and during menstrual bleeding
  • Pain during sex and bleeding after
  • Pain during bowel movements or urination
  • Irregular menstrual cycles
  • Pain in the lower back, belly, or pelvis


The doctor will ask about symptoms and health history. A pelvic exam will be done.

Pictures will be taken of the pelvis. This can be done with an ultrasound taken from the outside of the belly. It may also be done with a probe placed in vagina.

Surgery is needed to confirm the diagnosis. This can be done with a laparoscopy. During surgery, a sample of tissue may be taken for testing. This can be done with a biopsy.



Treatment depends on how severe the problems are. The goals are to ease pain and slow tissue growth. Options may be:


Medicine may be given to ease pain and swelling. It may be over the counter pain medicine, such as nonsteroidal anti-inflammatory drugs (NSAIDs).

Hormone medicine like birth control pills may also help. Birth control pills may be used to ease pain and shrink the size and number of growths. These problems often return when the pills are stopped. They will need to be stopped before trying to become pregnant.


Some growths can get in the way of future pregnancy. Surgery may be done to remove those growths.

Surgery may also be done for severe symptoms that do not respond well to other treatment. The goal will be too remove as much problem tissue as possible. The tissue can grow back later. Hormone therapy may be used after surgery to lower the chance of growths coming back.


There are no steps to prevent endometriosis.

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Edits to original content made by Denver Health.