Infertility due to Endometriosis
Classical studies suggested that 25% to 50% of infertile women have endometriosis and that 30% to 50% of women with endometriosis are infertile. Infertile women are 6 to 8 times more likely to have endometriosis than fertile women. Among women with pelvic pain, 30 to 80% will have endometriosis.
How does endometriosis cause infertility?
There is a definite association between endometriosis and infertility. However, it is not clearly established that endometriosis causes infertility. Most specialists will agree that there is a causal relationship between the two in patients with scar tissue or when the pelvic organs are distorted due to (severe) endometriosis. In these patients, surgery will improve the chances of pregnancy.
But, does minimal or mild endometriosis cause infertility? And how?
Several mechanisms have been proposed-
Distorted Pelvic Anatomy
When endometriosis causes scar tissue, this can interfere with the ability of the ovary to release eggs. Scar tissue also can prevent the tube from picking up the egg and transporting it.
Altered Peritoneal Function
Endometriosis induces inflammatory changes in the thin membrane lining the pelvis and abdominal cavity (peritoneum). This results in the release of substances (prostaglandins, proteases, cytokines, VEGF). These in turn mat have a negative impact on egg, sperm, embryo, or fallopian tube function.
Altered Hormonal and Cell-Mediated Function
This happens in the uterine lining. These abnormalities may alter the ability of the uterine lining to receive an embryo.
Hormonal and Ovulatory Abnormalities
Endometriosis patients may have hormonal imbalances that interfere with ovulation (luteinized unruptured follicle syndrome, luteal phase defect, abnormal follicular growth, premature as well as multiple LH surges).
Impaired Implantation
Endometriosis negatively impacts cell adhesion molecules (αvβ3 integrin) and other substances (L-selectin) that are necessary for the embryo to implant in the uterus.
Oocyte and Embryo Quality
In vitro fertilization studies have shown that patients with endometriosis can have poor quality eggs and embryos. Embryos derived from women with endometriosis appear to develop more slowly compared to those embryos derived from women with tubal disease.
Abnormal Uterotubal Transport
The fallopian tube may be functionally compromised in patients with endometriosis. Studies using a special technique (hysterosalpingoscintigraphy, HSSG) have shown that even when the tubes are patent; their ability to transport gametes (eggs, sperm, embryos) is compromised.
Also, investigations attempting to explain why patients with endometriosis are often infertile suggest that:
Finally, there may be an immunological factor involved in endometriosis. Endometriosis, indeed, may be an autoimmune disease. It is now widely accepted that the immune system, indeed, plays an important role in endometriosis-associated infertility.
- Endometriosis may release toxic substances which may harm embryos and/or their implantation capacity
- Patients with endometriosis may be at a higher risk for miscarriages, lowering their live birth chances
Finally, there may be an immunological factor involved in endometriosis. Endometriosis, indeed, may be an autoimmune disease. It is now widely accepted that the immune system, indeed, plays an important role in endometriosis-associated infertility.
Effects of Infertility on Women
Endometriosis affecting women’s fertility may cause a mixture of different feelings and emotions.
She may feel:
Some women feel pressured to have children as soon as possible to try and increase their chances of becoming pregnant. For women who don't feel ready to have children, do not have a partner, have not been in their relationship long, or are with a partner who is unwilling or not ready to have children, this situation can be overwhelming and upsetting.
Other women may be ready to have children and are trying to, but experience feelings of frustration, hopelessness and depression if over time a pregnancy does not occur naturally. It is often during investigations to determine the cause of not getting pregnant that the diagnosis of endometriosis is made.
Talking to a health practitioner, counsellor or psychologist can be really helpful in coping with these emotions and deciding what to do next.
She may feel:
- worried
- pressured
- confused
- upset
- angry
- stressed
- sad
- depressed
- grief
Some women feel pressured to have children as soon as possible to try and increase their chances of becoming pregnant. For women who don't feel ready to have children, do not have a partner, have not been in their relationship long, or are with a partner who is unwilling or not ready to have children, this situation can be overwhelming and upsetting.
Other women may be ready to have children and are trying to, but experience feelings of frustration, hopelessness and depression if over time a pregnancy does not occur naturally. It is often during investigations to determine the cause of not getting pregnant that the diagnosis of endometriosis is made.
Talking to a health practitioner, counsellor or psychologist can be really helpful in coping with these emotions and deciding what to do next.