Infertility and Endometriosis

Endometriosis is a major cause of infertility in women. In fact, nearly 50% of patients with endometriosis experience infertility. Dr. Serin Seckin dwelt on various aspects of endometriosis and infertility during her presentation at the 15^th Annual Endometriosis Patient Symposium held in New York City on March 2-3, 2024. 

How does endometriosis affect natural conception?

Dr. Serin Seckin started by giving an overview of how normal ovulation happens.

Essentially, for fertilization to occur, all organs of the reproductive tract must be functioning normally, she said.

Some of the important factors include spontaneous ovulation, good-quality eggs, normally functioning fallopian tubes, and a healthy uterus that allows the implantation of the embryo.

Endometriosis can cause distortions in pelvic anatomy in a lot of ways. This includes improper fallopian tube function, alteration of tubal proximity to ovulation, adhesions, decline in egg quality, and other hormonal abnormalities. Endometriosis can also cause impaired implantation, altered peritoneal function, and altered inflammatory pathways.

“But Having endometriosis does not mean you will not be able to have children”, Dr. Serin Seckin said.

How does altered peritoneal function during endometriosis affect fertility?

The peritoneal fluid is essential for proper egg capture by the fallopian tube after the ovary releases the egg. Patients with endometriosis have an increased peritoneal fluid volume. Consequently, the levels of inflammatory cytokines also increase.

The immune system produces autoantibodies, and a reduction of cell adhesion molecules occurs, both of which can affect implantation.

Adenomyosis (together or independent of endometriosis) can also affect the implantation of the embryo in the uterine endometrium.

Does endometriosis affect egg quality?

Ovarian endometriomas can affect egg quality. However, contradictory reports exist.

Though rare, eggs in endometrioma-affected ovaries can show altered chromosome numbers. The follicular fluid in the ruptured follicle can have high concentrations of cytokine and progesterone.

Testing the levels of anti-Mullerian hormone (AMH), and basal follicle-stimulating hormone (FSH) can give clues about ovarian reserve. Measuring antral follicle count (AFC) can also help. 

Research has shown that eggs harvested from women with endometriosis are more likely to fail in assisted reproductive techniques (ARTs) compared to those from healthy women.

The presence of endometrioma does not mean ovarian function has changed. However, your doctor might advise resection of endometriomas if they are too large, show worsening symptoms, prevent retrieval of eggs, or may be malignant.

“Getting a resection for large endometriomas is recommended”, Dr. Serin Seckin said, “but that’s a very personal conversation that has to be had with your doctor”.

How to treat infertility associated with endometriosis?

Treatment of infertility associated with endometriosis requires a personalized approach.

Removing endometriomas may not always be the right approach as it also implies removing the eggs and follicles. Therefore, the eggs have to be harvested before surgery. Surgery may also increase, decrease, or not affect ovarian reserves. In many cases, IVF may offer better outcomes compared to surgical interventions.

Studies comparing natural pregnancy outcomes with those of ARTs are quite old and present conflicting data. Some show no change in average delivery rate per cycle compared to endometriosis. Others, on the other hand, do show reduced pregnancy rates correlating with increased disease severity.

Does IVF help improve pregnancy rates?

Endometriosis lowers IVF outcomes too. However, the technique can still maximize conception rates, especially in those who have distorted pelvic anatomy.

There are no studies comparing the need for hormonal intervention before IVF.

Moreover, surgery before conception can improve fertility. However, studies so far show it is no more than what can IVF can be achieved with IVF. This opens up the question of whether to recommend surgery for an asymptomatic patient when things can be managed with IVF instead.