Endometriosis is a very common disease in women of reproductive age and is also linked to fertility problems. Approximately 30% to 50% of patients with endometriosis experience infertility and have some difficulty achieving a natural pregnancy.
This uterine condition is characterized by the presence of endometrial tissue outside the uterus, usually in the ovaries and fallopian tubes. Among its associated consequences are a decrease in ovarian reserve, lower oocyte and embryo quality in patients with endometriosis, as well as other conditions that can cause fertility problems.
However, assisted reproduction has greatly helped these women achieve pregnancy with endometriosis, especially through techniques such as in vitro fertilization (IVF) or even egg donation.
In the following video, embryologist Silvia Azaña explains how endometriosis affect a woman's fertility. However, you can later explore the topic in more detail by reading the article.
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Causes of infertility due to endometriosis
Although the causes of endometriosis are still somewhat unclear, several mechanisms have been proposed through which endometriosis may affect a woman’s fertility. Mainly, the ovaries and fallopian tubes are affected by the growth of endometrial tissue outside the uterus, which is characteristic of endometriosis.
Below are the main reasons why endometriosis may cause infertility. Additionally, it is very important to take into account the severity of endometriosis, as it is a key factor when trying to achieve a pregnancy.
Decreased ovarian reserve and poorer oocyte quality
In the ovary, endometrial adhesions and inflammation gradually destroy healthy tissue. This loss of healthy ovarian tissue affects the ovarian reserve of women with endometriosis, which can be reduced.
On the other hand, if surgery is performed to remove these endometriotic implants in the ovary (ovarian endometriomas or "chocolate" cysts), healthy tissue can also be damaged, which would lead to an impact on ovarian reserve.
Additionally, when endometriosis is present in the ovary, it creates an environment that is not conducive to normal follicle development and oocyte maturation. This is due to the presence of certain pro-inflammatory molecules and other factors that have a toxic effect.
Anatomical causes
When endometriosis appears in the fallopian tubes, it interferes with tubal patency. This prevents the egg from passing through and being transported along the tube once released from the ovary. Similarly, the passage of sperm is also hindered, so fertilization cannot occur.
On the other hand, besides affecting fallopian tube patency, their ability to capture the oocyte can also be impaired due to the presence of pelvic adhesions caused by endometrial tissue outside the uterus.
The fimbriae of the fallopian tube cannot interact with the egg and capture it, and therefore, the egg cannot reach the tube after ovulation. Thus, if the egg does not reach the fallopian tube, fertilization cannot take place.
Additionally, these adhesions caused by endometriosis can also alter the anatomy of the uterus, deforming it and even affecting its contraction pattern. If these uterine contractions are altered, the ascent of sperm to the fallopian tube is hindered, preventing fertilization of the egg.
Decreased endometrial receptivity
Female infertility due to endometriosis may also be caused by alterations in the endometrium itself within the uterine cavity.
This impact on the uterine endometrium could reduce endometrial receptivity and, therefore, hinder embryo implantation and the possibility of achieving a pregnancy.
One possible reason is that the levels of integrins (cell adhesion molecules necessary for implantation) may be altered, as well as the presence of an inflammatory environment.
Endometriosis and natural pregnancy
Endometriosis can be differentiated into 4 degrees depending on the location, quantity, depth and size of the endometrial implants:
- Grade I or minimum grade.
- Grade II or mild grade.
- Grade III or moderate grade.
- Grade IV or severe grade.
Women with more severe endometriosis will likely face greater difficulties in achieving pregnancy, and it may be necessary to resort to assisted reproductive treatment to accomplish it.
Pain relievers and hormone treatments are effective in relieving pain and regulating menstrual cycles. However, laparoscopic surgery will be necessary to improve fertility and increase the chance of pregnancy. Above all, they are effective treatments in mild endometriosis for a natural pregnancy.
Laparoscopic surgery is a minimally invasive technique in which a laparoscope is inserted to view the abdominal cavity through a small incision.
In the most severe cases of endometriosis, when women have endometriomas or ovarian cysts, also called chocolate cysts, it is advisable to perform a laparoscopic cystectomy to remove these cysts. This has been shown to increase pregnancy rates.
If you are interested in more in-depth information about the treatment of endometriosis, you can visit this article: Treatment of endometriosis: can it be cured?
Endometriosis and fertility treatments
If pregnancy does not come after surgery and after having tried for at least a year, assisted reproduction techniques are a hope for those women who see their motherhood at a distance.
To perform a PGD, one should undergo IVF as the main treatment. If you are looking for a clinic to get started, we recommend that you generate your individual Fertility Report now. It is a useful, simple tool that, in just 3 steps, will give you a list of the clinics that have passed our rigorous selection process. You will receive an email in your inbox with a report that contains tips and recommendations to get started.
Depending on the severity of the endometriosis and the evolution of the treatments, the appropriate techniques will be one or the other:
Artificial insemination.
Artificial insemination (AI) is indicated for young patients with mild endometriosis (grade I and II).
Normally, the patient is given hormones before insemination. These hormones used for ovarian stimulation improve the prognosis of women with endometriosis. Obviously, for AI to be effective, the tubes must be unobstructed and the sperm must be allowed to interact with the egg.
We advise you to access the following link to get all the information about this assisted reproduction technique: What Is Artificial Insemination (AI)? - Process, Cost & Types.
In vitro fertilization
IVF is the technique of choice for patients with endometriosis with greater involvement, i.e. type III or IV endometriosis. IVF is also indicated when AI has previously failed in women who had a better prognosis.
This reproductive option offers a higher gestation rate in women with endometriosis than if AI is performed. However, specialists recommend trying a first insemination in women who meet the requirements due to the simplicity of the technique.
If you want to continue reading more information about this topic, we recommend you to visit the following article: What Is In Vitro Fertilization (IVF)? - Process, Cost & Success Rates.
Ovodonation
In the IVF laboratory it has been observed that both eggs and embryos from patients with endometriosis have a worse morphology. In addition, fertilization and the subsequent development of the embryo have also been affected.
For this reason, women with severe endometriosis and/or several failed IVF cycles are forced to resort to ovodonation as a last option to have children. In fact, 10% of donor egg recipients are patients with endometriosis.
In addition, ovodonation is also indicated in cases where endometriomas of the ovary prevent follicular puncture to retrieve the eggs, or if these endometriomas have affected healthy ovarian tissue and, therefore, the ovarian reserve.
In this article, you can read more information about IVF with donated eggs: What is IVF with egg donation and how much does treatment cost?
Fertility preservation
Ovarian reserve is affected by endometriosis. This means that endometriosis can cause a decrease in the number of eggs available in a woman and, therefore, reduce over time (in addition to age) the chances of achieving pregnancy.
Since endometriosis is a progressive disease and a woman’s age also worsens infertility, it is recommended that women diagnosed with endometriosis cryopreserve their eggs if they wish to have children in the future, before the disease and the passage of time significantly reduce ovarian reserve.
Thanks to the vitrification technique, eggs can be stored "frozen" for an indefinite period of time, without altering the quality they had at the time of freezing.
You can read this article for more details about egg vitrification to preserve fertility: What is meant by egg vitrification and what are its advantages?
FAQs from users
Do all women with endometriosis have fertility problems?
No. Endometriosis can cause infertility, but not all women with endometriosis will experience infertility. It will depend mainly on the degree of involvement and the area(s) affected.
Which is more effective with mild endometriosis, IUI or IVF?
Intrauterine Insemination (IUI) is the treatment of choice for young patients with mild-to-moderate endometriosis (stages I and II). For this treatment to be possible, no blockage in the Fallopian tubes must exist. However, recent studies suggest that IUI may be ineffective in these cases. The latest European review on the average success rates during years 2016-2017 with AIH (artificial insemination by husband) are below 15% per cycle. So, in conclusion, opting for IUI in cases of mild-to-moderate endometriosis is possible in very particular cases where there is evidence that it might work.
In general, In Vitro Fertilization (IVF) is the first option for patients with a moderate or severe type of endometriosis (stages III and IV), as well as for women with previous failed cycles in spite of having a good prognosis initially.
Why does endometriosis cause infertility?
Since it is a disease whose cause is unknown and is related to other alterations and pathologies that can also affect fertility, it is difficult to establish why infertility can occur.
In any case, it has been observed that endometriosis can negatively affect the eggs (ovarian reserve), the fallopian tubes and embryo implantation.
Read more
Does endometriosis improve with pregnancy?
Yes, that's right. Pregnancy offers a protective effect against the endometriosis. In a pregnancy, a woman's menstrual cycle stops completely. This change leads to slower growth of the endometriosis. Therefore, during pregnancy, the woman often feels relief from the symptoms and pain caused by endometriosis. However, everything restarts once the woman gives birth.
Read more
Can endometriosis cause cancer?
Yes, it is possible, although unlikely. According to several studies, it is estimated that only 1% of endometriosis foci turn into malignant tumors.
However, these studies are still scarce, and more would be necessary to confirm the prevalence of endometriosis leading to cancer.
Read more
Can complications arise as a result of endometriosis?
Yes. The most common and prominent consequence of endometriosis is female infertility.
However, fertility problems are not the only consequence of this uterine pathology. Women with endometriosis may also present with chronic and prolonged pelvic pain, with the appearance of large cysts in the pelvis.
Other possible, though much less frequent, consequences of endometriosis are obstruction of the gastrointestinal or urinary tract, as well as cancer in the areas of endometriosis after menopause.
Is endometriosis synonymous with infertility?
No. Endometriosis is one potential cause of infertility in women. However, this does not mean that all women with endometriosis will have fertility problems. It is estimated that between 30% and 50% of women diagnosed with endometriosis have problems when trying to conceive. The difficulty in achieving a pregnancy will fundamentally depend on the severity of the endometriosis and from the different areas affected by endometrial tissue presence.
Read more
Suggested for you
Ovarian reserve can be affected as a result of ovarian endometriosis. To find out how this influences a woman's fertility, click here: How Many Eggs Does a Woman Have? - Your Egg Count by Age.
We have talked about fertility preservation as a method to avoid the deterioration of oocyte quality. If you want to know what this method consists of and the prices it has in Spain, you can continue reading here: Fertility Preservation - Cost & Options for Retaining Your Fertility.
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FAQs from users: 'Do all women with endometriosis have fertility problems?', 'Which is more effective with mild endometriosis, IUI or IVF?', 'Does endometriosis reduce ovarian reserve and oocyte quality?', 'Why does endometriosis cause infertility?', 'Why does endometriosis affect Fallopian tube permeability?', 'Does endometriosis improve with pregnancy?', 'Is endometrial receptivity affected in endometriosis?', 'Can endometriosis cause cancer?', 'Can complications arise as a result of endometriosis?' and 'Is endometriosis synonymous with infertility?'.
