The uterus (Latin for womb) has an interior lining, or endometrium, consisting of special cells that will support and nurture a fertilized egg that attaches there in the first stages of pregnancy. The endometrial cells shed every month during menstruation. Endometriosis is a condition in which these endometrial cells are found outside the womb. The wayward endometrial tissue typically grows in various locations, or on various organs, in the pelvis; however, it can also travel and attach to virtually any location in the body.
A number of theories may explain this spread of endometrial tissue (see box below), but the exact cause has yet to be confirmed. By processes still under study, these cells migrate out into the pelvic space, where they, in effect, metastasize to such locations as the exterior of the uterus, ovary or bowel. They may also grow in the fallopian tubes and affect fertility (see image below) by blocking these tubes.
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Symptoms Can Be Cyclical and Widespread
Endometrial tissue found outside the uterus behaves much as does normal endometrial tissue during a woman's monthly cycle, as these cells are programmed to build up and shed each month in response to hormones. For this reason, individuals with endometriosis experience monthly proliferation of endometrial tissue, followed by internal bleeding and fluid build up causing pain and pressure.
Endometriosis has been found in every area of the body, including the lungs and, rarely, the brain and even as far as the globe of the eye. Misplaced endometrial growth can create scar tissue, adhesions and chronic discomfort, and can interfere with organ function, including in the reproductive system (see below). In a less common form of endometriosis, called adenomyosis or internal endometriosis, the endometrial tissue grows within the muscular uterine wall.
Endometriosis is not simple to identify and requires experience to diagnose. Radiologic studies can help to eliminate other possible diagnoses, but only visual inspection, including biopsy of a tissue sample for analysis in the lab, will fully confirm its presence. The specialist accomplishes this with a minor, outpatient surgical procedure-laparoscopy, which involves a small incision in the abdomen to introduce an endoscope and instruments.
Shrinking or Removing Errant Endometrial Tissue
Treatment seeks to remove or shrink endometrial growths, to relieve painful symptoms and often to improve fertility. Medical options include use of an injection that significantly reduces estrogen levels in the body. This can stop menstruation and allow the body to attack the misplaced tissue, ridding the pelvic area of endometrial growth. Side effects may include menopause-like symptoms such as hot flashes and bone loss.
In some cases, the gynecologic surgeon will use laparoscopy again, this time to destroy (ablate) or excise (cut away and remove) the abnormal tissue. Surgical ablative options include use of heat applied by different forms of energy to destroy the unwanted tissue. In electrosurgery, the surgeon uses electrocauterization, a process in which electricity passed through a metal probe generates heat to destroy the tissue. Tools for ablation also include lasers that generate heat to vaporize the cells.
If portions of endometrial tissue are large and attached to an organ or ligament. they may be too large to burn in which case the surgeon can remove them by surgical resection. Each case requires customized treatment, and at Lourdes patients may benefit from robotic-assisted surgery. This advanced approach gives the surgical team greater ability to preserve a woman's uterus, even in severe cases of endomteriosis. Surgical preparation my include using medicines to shrink the tissue first.
If other options fail or are not appropriate the specialist may recommend a hysterectomy, often with removal of the uterus, fallopian tubes and ovaries.
Endometriosis and Fertility
Endometriosis can prevent normal female fertilization, potentially by a number of different mechanisms, including physical and hormonal means. Reproductive endocrinologists commonly discover the condition in women with fertility problems.
Scarring and adhesions in the pelvis, caused by endometrial tissue, can easily place enough physical tension or pressure on fallopian tubes to block these tubes. This can prevent the tubes from capturing eggs or transporting them to the uterus.
Endometrial tissue may also secrete fluids that prevent fertilization. These conditions may affect egg or sperm or both, preventing conception.
With their high level of technical skills, Lourdes' experienced gynecologic surgeons have success in using laparoscopic surgery to remove these endometrial barriers to fertility. Pregnancy rates following surgery are related to the severity of the endometriosis. They can be as high as 80 percent for groups of patients with less-severe cases.