What is endometriosis?

A teen girl or woman has endometriosis when the endometrium, the tissue that normally lines her uterus, grows in other places, such as the fallopian tubes, ovaries, or pelvic tissue. This misplaced tissue can cause serious pelvic pain or painful menstrual periods (dysmenorrhea).

When endometrium grows in other places, it functions like it does in the uterus by thickening, breaking down, and bleeding away each month. Since there is nowhere for this blood to go, it stays trapped in the body, and this can cause painful cysts and scar tissue. Endometriosis affects an estimated 5.5 million teen girls and women in North America.

Without treatment, endometriosis can lead to infertility. Thirty to 40 percent of women with endometriosis are infertile. However, there are successful fertility treatments for women with newly discovered endometriosis, and early treatment during adolescence can prevent infertility.

What are the symptoms of endometriosis?

Endometriosis can be mild, moderate, or severe. Some teen girls or women experience no symptoms at all, but it tends to get worse over time. If you or your daughter has endometriosis, you could be experiencing:

Painful periods (dysmenorrhea)

  • Pelvic pain may include lower back and abdominal pain.
  • The level of pain may not match the severity of the endometriosis.
  • Some teen girls or women have mild endometriosis and severe pain, while others have more severe endometriosis and little pain.

Chronic pelvic pain

  • Pain may be accompanied by frequent urination, diarrhea, or constipation.
  • excessive bleeding or bleeding between periods


Endometriosis can cause scar tissue that can make it hard for a woman to get pregnant or cause infertility. Sometimes endometriosis is only diagnosed when a woman is seeking infertility treatment.

What causes endometriosis?

The exact cause of endometriosis is unknown, although we do know that it runs in families. The three most accepted theories of endometriosis are:

  • Sampson's Theory: Menstrual blood filled with endometrial cells flows backward through the fallopian tubes and attaches to other surfaces outside the uterus.
  • Meyer's Theory: Cells with the potential to become endometrial cells are present in the abdomen at birth, but don't change into endometrial cells until later in a woman's life.
  • Vascular Theory: The endometrial tissue travels through the blood vessels to other tissues. It implants and grows, just as metastasizing cancer cells do. (Endometrial cells have no more chance of becoming cancerous than any other cell.)

How we care for endometriosis

The Division of Gynecology at Boston Children's Hospital provides expert medical care, special health education programs, and a wealth of information to young women who are living with endometriosis. Pelvic pain and painful menstruation can be distressing for teens. We provide age-appropriate treatment, counseling, and special health education programs, including supervised online chats.