Endometriosis and Fertility

Endometriosis is associated with an increased risk of having difficulty becoming pregnant, or infertility. Studies have shown that the amount of endometriosis that is seen at the time of laparoscopy is linked to future fertility.

There is a staging system for evaluating endometriosis:

  • Stage I endometriosis (minimal disease): There are few small implants (specs) of endometriosis, with no scar tissue seen.
  • Stage II endometriosis (mild disease): There are more implants of endometriosis, but less than 2 inches of the abdomen is involved and there is no scar tissue.
  • Stage III endometriosis (moderate disease): There is quite a bit of endometriosis in the abdomen which may be deep and may create pockets of endometriotic fluid (chocolate cysts, or endometriomas) in the ovaries. There may be scar tissue around the tubes or ovaries.
  • Stage IV endometriosis: A great deal of endometriotic implants, possibly large endometriotic cysts in the ovaries, possible scar tissue between the uterus and the rectum (lower part of the intestines), and around the ovaries or fallopian tubes

Surgical Treatment of Endometriosis and Fertility

Women with Stage I and II endometriosis may become pregnant on their own, however, medical studies do suggest that if laparoscopy is done in women who have infertility, they are more likely to have endometriosis than women who become pregnant with no difficulty. There is some evidence that pregnancy rates may improve if Stage I or II endometriosis is removed surgically, however some data shows that this does not help.

In general, when women are young (less than 35 years old) it is reasonable to remove any visible endometriosis to see if pregnancy occurs. If women are 35 or older, other fertility treatments are recommended instead of laparoscopy (see below). If Stage III or IV endometriosis is present, pregnancy rates are higher after surgery is performed to remove scar tissue or large endometriotic cysts. If pregnancy does not occur within 6 months after surgical treatment of endometriosis, other fertility treatments should be discussed.

Unfortunately, some women with endometriosis can have cysts that come back. If cysts are removed over and over, this can cause a loss of eggs from the ovaries, and can make it harder to become pregnant.

Medical Treatment of Endometriosis–related Infertility

Before starting any fertility treatment a complete fertility evaluation is performed. This can include hormone and other blood testing and checking the partner’s sperm count. Medical treatments depend on the stage of a patient's endometriosis:

Stage I-II endometriosis Clomiphene IUI treatment

In order to improve the likelihood of pregnancy clomiphene citrate, a fertility medication, is given for 5 days soon after the menstrual period starts. At the time the egg is released from the ovary (ovulation), the male partner produces a sperm sample by masturbating into a sterile cup. The sperm is brought to the fertility laboratory and processed. The woman then comes into the office at the time she is ovulating for the sperm to be placed into her uterus with a thin tube. This is done during a speculum exam and feels similar to a Pap test. The likelihood of having a baby with one treatment of clomiphene/ IUI is approximately 10% for women less than 40 years old.

If this treatment is not successful after three or so months, the next step is 1) the use of injected infertility medications with IUI, or 2) in vitro fertilization.

Stage III-IV endometriosis

If pregnancy does not happen within six to 12 months after surgical treatment of moderate to severe endometriosis, in vitro fertilization is generally recommended. In some cases the fallopian tubes are found to be blocked, and/ or scar tissue is very severe. In some situations your doctor may recommend going straight to fertility treatment with in vitro fertilization.

In-vitro fertilization (IVF)

Before you start this treatment, your doctor will explain the chance of in vitro fertilization working for you, based on your age and hormone testing.

This treatment requires a woman to take small injections of fertility medications which cause many eggs to grow in the ovaries within fluid pockets called follicles. These follicles are watched with blood and ultrasound tests. When the follicles are a certain size, the eggs are ready to be removed from the ovaries. This is done under a light sleeping medication (anesthesia). Using a needle that is guided by ultrasound, and passed through the vaginal wall into the ovaries, the eggs that have grown are removed. This process takes about 10 minutes. The eggs are then placed in dishes with sperm in the fertility laboratory. Most will fertilize and grow into embryos.

A few days after the eggs are removed from the ovaries the woman comes back to the fertility clinic and one to a few embryos are placed into the uterus with a thin tube, through the cervix, during a speculum exam. This feels similar to a Pap test. The likelihood of a pregnancy from one try of in vitro fertilization ranges from 50% or higher for women in their 20s, to only 10% for women in their 40s.

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