Blockage of the fallopian tubes can occur as a result of serious infection, congenital abnormalities, scarring from previous surgery, or endometriosis. Endometriosis is a major cause of infertility and may be present with no symptoms. Some studies indicate that endometriosis decreases pregnancy rates even though there may be little visible organ damage. Endometrial tissue attaches to organs, grows, divides, and can penetrate causing obstruction and other types of damage. Endometrial tissue is dependent upon estrogen for growth. The medications used to treat endometriosis lower estrogen levels, thus "starving" the aberrant tissue.
Endometriosis is a benign disease defined by the presence of ectopic (outside the uterus) endometrial tissue and stroma that can be associated with pelvic pain and infertility. Endometriosis exhibits a broad spectrum of clinical manifestations, is prone to progression and recurrence, and often presents difficult clinical management problems for women and their clinicians. Endometriosis is a major cause of infertility and may be present with no symptoms. Some studies indicate that endometriosis decreases pregnancy rates even though there may be little visible organ damage.
Most estimates of the prevalence of endometriosis range from 5% - 20% among women with pelvic pain and 20% - 40% among infertile women; a general prevalence of 3% - 10% in reproductive - aged women is likely.
The causes of endometriosis are not clearly understood, although the most accepted one is the theory of retrograde (back flow) menstruation and implantation. Endometriosis tends to cluster within families. It is six to seven times more prevalent among the first degree relatives of affected women than in the general population.
Endometriosis is strongly associated with infertility. In women with advanced stages of endometriosis, grossly distorted pelvic anatomy or tubal occlusion offers a logical explanation, but in women with milder disease, any mechanisms that may be responsible are less obvious. Indeed, whether minimal and mild degrees of disease can be regarded as a cause of infertility remains highly controversial. The infertility associated with endometriosis has been attributed to three primary mechanisms: distorted adnexal anatomy that inhibits or prevents ovum capture after ovulation, interference with oocyte development or early embryogenesis, and reduced endometrial receptivity.
Traditional medical therapies for endometriosis have reduced or eliminated cyclic menstruation. These include multiple medications with different side - effects: danazol, progestins, oral contraceptives, and GnRH agonists (Lupron). Overall, the effects of medical treatments on the volume of endometriosis are similar, but medical treatments are not effective for all but the smallest of ovarian endometriomas (less than 1 cm). Treatment with danazol or a GnRH agonist may decrease the size of endometriomas but does not eliminate them.
The objectives of surgical treatment of endometriosis is to restore normal anatomy, to excise or destroy all visible disease, and to prevent or delay recurrence of disease. Surgery for the treatment of endometriosis can be performed via laparotomy or laparoscopy. Laparoscopy offers the advantages of better visualization, less tissue trauma and desiccation, smaller incisions, and a shorter postoperative recovery. Deeply infiltrating endometriosis involving the rectovaginal septum requires extensive surgery. The Endometriosis Association is an international organization that provides education and support for women with endometriosis. IVF is the most effective treatment for infertility patients with endometriosis.