Endometriosis is an often painful condition in which tissue that normally lines the inside of the uterus (the endometrium) grows outside the uterus. In general, endometriosis affects the ovaries, fallopian tubes, and the tissue lining the pelvis. Rarely, endometrial tissue expands beyond the pelvic organs.
When endometriosis is present, out-of-place endometrial tissue continues to act as it normally would: it thickens, breaks down, and bleeds with each menstrual cycle. Since this tissue that is out of place has no way out of the body, it becomes trapped. When endometriosis affects the ovaries, cysts called endometriomas can form. The surrounding tissue can become irritated and can ultimately develop scar tissue and adhesions (abnormal bands of fibrous tissue that can cause pelvic tissues and organs to attach to each other).
Endometriosis causes pain (sometimes severe), especially during the menstrual period. Fertility problems can also occur. Fortunately, there are effective treatments.
The first symptom of endometriosis is pelvic pain, often associated with the menstrual period. Although many women have cramps during their menstrual period, women with endometriosis often describe menstrual pain that is much worse than usual. They also tend to report that the pain increases over time.
Common signs and symptoms of endometriosis include the following:
- Painful periods (dysmenorrhea) Pelvic pains and cramps may begin before the period and extend over several days of the period. You may also have pain in your lower back and abdomen.
- Painful sexual intercourse. When you have endometriosis, it is common to feel pain during or after sex.
- Pain during bowel movements or urination. You will most likely have these symptoms during your menstrual period.
- Excessive bleeding. Sometimes you may have heavy periods (menorrhagia) or bleeding between periods (menometrorrhagia).
- Sterility. Endometriosis is usually found in women seeking treatment for infertility.
- Other symptoms. You may also feel tired and have diarrhea, constipation, gas, or nausea, especially during menstrual periods.
The intensity of the pain is not necessarily a reliable indicator of the severity of the condition. Some women with mild endometriosis have severe pain, while others with advanced endometriosis have little or no pain.
Sometimes endometriosis is mistaken for other conditions that also cause pelvic pain, such as pelvic inflammatory disease or ovarian cysts. It can also be confused with irritable bowel syndrome (IBS), a condition that causes episodes of diarrhea, constipation, and abdominal cramps. IBS can add to endometriosis, which complicates diagnosis.
When to see your doctor
Talk to your doctor if you have signs and symptoms that could be indicating endometriosis.
Endometriosis can be difficult to treat. Early diagnosis, a multidisciplinary medical team, and a clear understanding of your diagnosis will help control symptoms.
Fertilization of an ovary and implantation in the uterus
Fertilization and implantation
The most important complication of endometriosis is alterations in fertility. About one-third to one-half of women with endometriosis have difficulty getting pregnant.
For this to happen, the ovaries must release an ovary that travels through the nearest fallopian tube, is fertilized by a sperm, and attaches to the wall of the uterus to begin to develop. Endometriosis can block the tube and prevent the ovary and sperm from joining. However, the condition also appears to affect fertility in less direct ways, such as damaging the sperm or ovary.
Even so, many women with mild to moderate endometriosis can still conceive and carry the pregnancy to term. Doctors sometimes advise women with endometriosis not to delay having children because the condition may get worse over time.