Endometriosis is a chronic, inflammatory relatively common condition, determined by the presence of endometrial glands and stroma outside the uterus and is associated with both pelvic pain and infertility. It is estimated at 5-10%, which corresponds to about 176 million women affected worldwide. It is also estimated that this affects about one in 10 women during their reproductive ages (usually between the ages of 15 and 49). Ectopic endometrial tissue is usually located in the pelvic area, but can appear anywhere in the body.
Thus, the eutopic and ectopic endometrium of women with endometriosis differs from normal endometrium in at least three ways, showing (1) a high local production of estrogens (estrogen dependent disorder), (2) high local production of prostaglandins, and (3) resistance to the action of progesterone (prostaglandins responsible for pain and inflammation).
More than one mechanism explains all cases of endometriosis, and each appears to contribute, at least to some extent. It is widely believed that lesions occur through retrograde loss of endometrial tissue during menstruation, coelomic metaplasia, and lymphatic spread in immunologically and genetically susceptible people. Although its main cause is uncertain, it is likely to be multifactorial, including genetic factors with possible epigenetic influences, possibly promoted through environmental exposure.
Management of Disease
Currently, there is no cure for endometriosis; endometriosis treatment focuses on the treatment of symptoms. Endometriosis treatment may be an expected or limited use of analgesics or can involve one or a combination of medical procedures, conservative or definitive surgery, or a combination of medical and surgical treatment, depending on its clinical manifestations. When the disease is less pronounced, endometriosis treatment can effectively control pain in most women, but does not affect fertility. Patients should receive individual care benefits from a multidisciplinary network of experts competent enough to provide advice on endometriosis treatment and its associated symptoms, based on best available evidence, their extensive experience and their transparent record of success rates.
Influence on Fertility
Endometriosis is strongly associated with infertility; from 20% to 40% of infertile women have the disease, probably due to a violation of tubo-ovarian function, distorted by adnexal anatomy, which inhibits or prevents ovum capture after ovulation. The presence of an ovarian endometrioma, a chronic inflammation that worsens the function of the ovaries, tubes, or endometrium, leading to abnormalities in folliculogenesis, fertilization, or implantation, possibly to a decline in oocyte quality. The role of endometriosis and, therefore, endometriosis treatment, in infertility is clearer, when endometrial lesions has changed the pelvic anatomy (for example, with pelvic adhesions). The mechanisms by which infertility occurs in women with mild illness are not entirely understood.
Both endometriosis and adenomyosis (lesions occurring in the uterine-intramural-muscular layer) reduce the likelihood of successful assisted reproductive treatment.
While the relationship between endometriosis and infertility remains unclear, there is strong evidence that potential or diagnosed infertility can cause a significant emotional and financial burden for women.
Intrauterine insemination (IUI) in combination with ovarian stimulation is an effective option for women with minimal-moderate endometriosis if the fallopian tubes are normal. However, IVF is usually offered in the first line, preferably IUI, when the endometriosis is more severe, and the tubular function is impaired, either in the context of advanced female age and/or a decline in sperm quality.
Endometriosis can adversely affect the success rates of IVF compared to other causes of infertility. However, IVF is recommended as an infertility treatment, as part of endometriosis treatment, for women with endometriosis, especially if the fallopian tube function is impaired or there are other factors of infertility such as male factor.
There is insufficient evidence to support the usual fertility preservation in women with endometriosis. Endometriosis can be an indicator for fertility preservation. Nevertheless, reliable clinical data and cost-benefit analysis are justified before the introduction of its use in routine clinical practice.
Patients affected by each iatrogenic or pathological disease that are known to compromise ovarian function have been recognized as potential candidates for fertility preservation. Among them, women with endometriosis can be a particularly suitable group, as they are known to be at increased risk of infertility and an earlier deterioration of the ovaries.
Fertility preservation may be of interest to women with endometriosis, especially in women with bilateral non-operated endometriomas and those who previously removed unilateral endometriomas and needed surgical intervention for contralateral relapse.
The evaluation should be comprehensive and should take into account other factors, such as the family history of premature ovarian failure, BMI, alcohol consumption, smoking and biomarkers of the ovarian reserve. Given the possible options for endometriosis treatment, egg banking should now be preferred than ovarian cortex freezing due to the more solid evidence available. However, the latter option should be considered as an alternative possibility, especially when a radical operation is envisaged.