Endometriosis and Infertility
One of the clinical manifestations of endometriosis is a difficulty to conceive. This is related to inflammatory or immunologic reaction impairing ovulation, tubal function and endometrial function even in the early stages of endometriosis (stage I and II). Sperm function can also be affected. In more advanced stages (stage III and IV), adhesions around the Fallopian tube or ovary play an additional factor in infertility. In those stages, the anatomy is distorted interfering gamete function, fertilization or myometrial contraction.
Endometriosis is diagnosed by visualization during surgery and the diagnosis is established by histopathological examination of the excised tissue. Today, most surgery is performed by laparoscopy which is a less invasive procedure than open surgery. Endometriosis can be detected, staged and treated at the same setting. Staging of endometriosis is performed using the classification of the American Society of Reproductive Medicine.
Ovarian endometriosis can be associated with cyst formation (chocolate-colored cyst or endometrioma). Transvaginal ultrasound examination provides a distinct feature of the blood filled cyst. The differential diagnosis includes endometrioma or hemorrhagic cyst. MRI will be able to detect endometriosis plaque or nodule. Yet, small endometriotic implants cannot be seen.
In the management of infertility, one should perform basic infertility tests including semen analysis, test for tubal patency such as hysterosalpingograpy or hysterosonography and documentation of ovulation. In our reproductive center, we routinely perform transvaginal ultrasound examination to rule out uterine or ovarian pathology as well as to measure the antral follicle count (AFC). In women over 35 years old or in those with irregular menstruation, one should measure serum gonadotropin, prolactin, thyroid hormone profiles, ovarian steroids as well as anti-mullerian hormone (AMH). Treatment is based on the results of those tests.
The classical symptoms of patients with endometriosis are dysmenorrhea, dyspareunia, dyschezia or chronic pelvic pain. However, not all women with these symptoms have endometriosis on laparoscopic examination. We perform laparoscopy only in infertile women with severe symptoms and in those with endometrioma on imaging. Since the main objective is conception, we first treat women with possible endometriosis with superovulation using letrozole and intra-uterine insemination for 3 cycles. However, those over 35 years old or with diminished ovarian reserve are better treated with in-vitro fertilization (IVF). IVF is more effective than superovulation and IUI, however it is costly.
IVF is performed even in the presence of ovarian endometrioma providing that its presence does not interfere with oocyte retrieval. While stage I and II endometriosis do not affect IVF outcome, studies evaluating the effects of stage III or IV endometriosis have been mixed. Yet, in a meta-analysis involving 78 studies (over 20,000 women), Barbosa et al (2014) reported comparable IVF outcome in women with early and late stage endometriosis. It suggests that the presence of endometriosis does not impair IVF outcome. Oocyte retrieval in the presence of endometrioma has been associated with the development of tubo-ovarian abscess. Antibiotics coverage is therefore recommended. Generally, we transfer one embryo and excess embryos are frozen for future use.
Laparoscopic treatment of endometriosis stage I and II is associated with a slightly higher pregnancy rate and this is independent on the technique used (ablation or excision). Instead of just “burning” the endometriosis implants, we routinely excise the lesions. This leads to a more complete removal of the endometriosis especially in those with pelvic pain. Surgical treatment of infertile women with stage III or IV endometriosis is slightly different than in those who have completed their family. Here, one has to be careful of not removing normal ovarian tissue that can lead to reduced ovarian reserve.
Ovarian endometrioma can be removed by excision stripping the “cyst wall” or by just draining the content of the cyst and vaporizing the “cyst wall” either with laser or electrosurgery (fenestration and coagulation). Fenestration and coagulation, however is associated with higher recurrence rate. We prefer to excise the ovarian endometrioma. However, when stripping is difficult due to intimate attachment between the “cyst wall” and the ovarian tissue, the procedure is converted to coagulation of the “cyst wall”. As we have previously published, this procedure does not affect ovarian reserve. In women with chronic pelvic pain and not interested in fertility, surgery is perform to eradicate the disease.
Today, many women seek fertility treatment in mid and late thirties. Due to the decreasing fertility, hormonal suppression in these women is rarely prescribed. It delays fertility. Surgery if needed follows by fertility treatment is a better option.
The main objective of endometriosis treatment in infertile women is conception and not eradication of endometriosis.
Not all infertile women with possible endometriosis need surgery.
Medical treatment by hormonal suppression delays fertility.
If the presence of ovarian endometrioma does not interfere with egg retrieval, surgery to remove the endometrioma is not needed.
Surgery for ovarian endometrioma in infertile patients has to be performed carefully. Removal of “ovarian cyst wall” when the cyst wall is severely adhered to the normal ovarian tissue might be associated with reduced ovarian reserve decreasing the chance of conception.
In general, the outcome of IVF treatment is not impaired by the presence of endometriosis.
About Dr. Togas Tulandi: Dr Tulandi is one of Canada’s most published and cited researchers in the field of reproductive medicine. He is a Professor and Chair of the Department of Ob/Gyn at McGill University in Montreal, Quebec. He is also the Milton Leong Chair in Reproductive Medicine and an inaugural Board Member of the Canadian Society for the Advancement of Gynecologic Excellence (CanSAGE)
Legend (Figures courtesy of Dr. S. Singh, Ottawa)
Fig. 1. Endometriosis along the anterior cul de sac (classic black, brown and white lesions)
Fig. 2. Post laparoscopic excision of superficial endometriosis from Fig. 1.