Endometriosis is a common condition that sometimes causes pelvic pain or infertility. It affects approximately 1 in 10 women. Despite being common, it is often misdiagnosed or overlooked because the characteristic symptoms are often similar to those of other diseases, such as irritable bowel syndrome, pelvic inflammatory disease, ovarian cysts and interstitial cystitis. Sometimes endometriosis can produce significant scarring and infertility with no symptoms whatsoever.

For many women endometriosis can cause significant pain and debilitation. The pain is typically a cyclic pelvic pain but can also occur in the abdomen or lower back.  It can be severe enough that women are unable to go to school or work, and are unable to conduct their daily lives in a normal fashion. While endometriosis can be debilitating, it is not life-threatening.

Endometriosis is a known cause of infertility. There are medications, surgical procedures and assisted reproductive technologies available to assist you in becoming pregnant. These therapies are well established and highly effective. Additionally, there are a multitude of different options available to treat pain associated with endometriosis. Surgical options can remove endometriosis while medical therapies can often stop the progression of endometriosis, cause it to regress and alleviate the pain.

Endometriosis can be extremely challenging, both physically and emotionally. At the Yale Fertility Center, we offer effective testing for this condition as well as a large number of options for its treatment, management, and counseling.

Common Questions about Endometriosis

Endometriosis results when the tissue that normally lines the inside of the uterus, called the endometrium, grows in places of the body where it is not normally found. It may spread to the ovaries, fallopian tubes, uterus, bowel or bladder. It may be found anywhere within the abdominal cavity. Rarely endometriosis can be found in remote areas including the lung, brain and nose. Most endometriosis arises from small fragments of the lining of the uterus that are shed with the menstrual period. These fragments can travel out of the fallopian tubes rather than flowing out of the body with the menstrual flow. Because this tissue is nearly identical to that found in the uterus, it responds to hormonal changes as would the uterine lining. During the menstrual period the tissue breaks down and shedding of this tissue results in menstrual bleeding into surrounding areas that causes pain and inflammation, typically just prior to and at the time of the menstrual period. With continued damage from repetitive bleeding, scars and adhesions begin to form which pull organs together resulting in tension pressure and pain.

A typical menstrual cycle takes approximately 25 to 32 days. The menstrual cycle is regulated by production of hormones. Estrogen is produced in the beginning of the cycle, and after ovulation progesterone is produced. These hormones prepare the uterus for pregnancy by thickening and developing the endometrium or lining of the uterus. When you have endometriosis, the misplaced tissue in the abdominal cavity and other areas also thicken similarly to the lining of the uterus. When pregnancy does not occur, the uterus and the misplaced tissue shed leaving debris and blood in the abdominal cavity. As this misplaced lining grows, it can scar, pull and stretch surrounding tissues causing pain. As the fluid, blood and cellular debris are shed from this tissue during the menses, the retained menstrual fluid causes irritation, inflammation and pain. This inflammation and irritating fluid can become glue-like so that it causes one organ to adhere to another. Subsequently, any movement, including that that occurs during ovulation, intercourse or bowel movements can be painful as tissues pull and tug on one another, stretching them and distorting them. Even when the tissue heals after bleeding, the scarring can be permanent and cause long term pain.

Endometriosis can also be encapsulated in the ovary forming cysts known as endometriomas or ‘chocolate’ cysts. This name comes from the fact that the menstrual fluid that builds up over many months or years takes on a thick brown chocolate syrup like consistency.

Any woman is susceptible. Endometriosis strikes approximately 1 in 10 women. Often the pain begins prior to the first period. Pain may begin to occur at any time from the time of the first period through the mid-40's. It most commonly first noticed in the 20's and early 30's. However, we believe that endometriosis often starts with subtle pain and may go undiagnosed for years prior to becoming severe enough that appropriate testing is done. You are at higher risk for endometriosis if someone in your family has had endometriosis. There is a genetic component to the disease. Women with a mother/sister/aunt who have endometriosis are more than twice as likely to develop the disease and are also more likely to have a more severe form of the disease. Women who have not had children, who have heavier prolonged periods or started having their periods at an early age are also more susceptible. The use of oral contraceptives often will help suppress endometriosis. Pregnancy can also suppress endometriosis.

It is not known why some women develop endometriosis and others do not although there is a strong hereditary component. As described above, one of the main causes of endometriosis is the flow of menses backwards through the fallopian tubes in what is called retrograde menstruation. The woman's menstrual flow through the fallopian tubes results in small pieces of endometrium growing in the abdominal cavity. These pieces of endometrial tissue can continue to grow and multiply. As all bleeding that result from these lesions is then shed into the abdominal cavity, there is the opportunity for many more lesions to form over time. 

Retrograde menstruation does not completely explain endometriosis. Almost all women have small amounts of retrograde menstruation through the fallopian tubes, yet only about 10% develop endometriosis. Some women have natural defenses against the cells implanting elsewhere. There are likely to be genetic factors that prevent an individual from rejecting or clearing these cells. Defects in immune system may also prevent one from destroying these cells. Heavy menses with large amounts of backwards flow can increase the likelihood of endometriosis and overwhelm ones natural defenses, even if one is not at risk because of genetic factors. Environmental factors may also play a role.

There are many symptoms of endometriosis and they vary widely. Some women may have no symptoms at all. The only symptom may be infertility and the disease will go unnoticed until a woman wants to conceive. Others may have pain that often starts gradually and becomes more and more severe. Pain is typically cyclic, occurring before and during menses. However, over time with scar formation, the pain can become constant and no longer fluctuate with the menstrual cycles. The pain is generally dependent on the extent of the disease and the amount of scarring and adhesions present. Some may have both pain and infertility associated with endometriosis.


Pain is the most common symptom of endometriosis. The pain includes:

  • Severe menstrual cramps
  • Pain with ovulation
  • Low back pain
  • Pain with urination
  • Pain with bowel movements
  • Pain with intercourse
  • Abdominal pain
  • Bloating 


While most women with endometriosis have normal menstrual flow, some can have predictably heavy periods, irregular periods, or prolonged periods, and may have spotting outside the time of normal menstruation.

Symptoms other than pain include: infertility, irregular bowel activity including diarrhea or constipation, bladder irritation, bloating, tiredness, and depression. Because of the varied nature of the symptoms, endometriosis is often misdiagnosed. The pain in the bowel or bladder may be confused with irritable bowel syndrome or interstitial cystitis.

The only way to tell with 100% certainty if one has endometriosis is to perform a laparoscopy. A laparoscopy is a surgical procedure where a telescope is inserted through the bellybutton and a physician can visualize the endometriosis. While visualizing endometriosis, the endometriosis can also be surgically removed.

It is not always necessary to perform a surgical procedure to determine if one has endometriosis. Endometriosis should be suspected in anyone with cyclic pain. Any pain in someone with endometriosis in the family is suggestive of the disease in that individual. Classic pain along with either findings on examination or on an ultrasound may be enough to make the presumptive diagnosis of endometriosis and begin treatment.

Mild symptoms of endometriosis are often overlooked. Typically, it is years from the time that a woman begins to experience pain or symptoms of endometriosis to the time the diagnosis is made. If you suspect you have endometriosis, or are beginning to experience more painful periods or non-cyclic pelvic pain, it is important that you discuss these findings with a gynecologist who specializes in this disease.

Approximately 1/3 of women with infertility have endometriosis. In some women this is the sole problem responsible for their infertility; in others it is an additional contributor. Many women with endometriosis don’t experience pain and do not know that they have the condition until they first try to become pregnant.

Endometriosis causes infertility by many mechanisms. The inflammation and scarring from endometriosis can block the fallopian tubes or damage and scar the ovaries. This can prevent the egg from being released to the ovary or from reaching and traveling through the fallopian tube. Endometriosis can also make it more difficult for the sperm to travel within the fallopian tube to reach the egg. Endometriosis also affects the lining of the uterus. The endometrium in women with endometriosis is less prone to accept embryos and allow them to attach to this lining. The inflammation and cyst within the ovary often don’t allow the eggs to develop properly. They are less likely to be fertilized and less likely to result in an embryo.

There are many treatment options available for a woman with endometriosis to become pregnant. Some women may need simple medications while others may need surgery or assisted reproductive technologies. These are discussed below.

How is Endometriosis Treated?

There are a large variety of treatments available for the many symptoms and manifestations of this disease. Treatment should be given in an individualized and personalized approach. One should consider seeking advice of a physician with expertise in endometriosis prior to the onset of symptoms to prevent the disease if one has any close family members with the disease. In treating pain in women with endometriosis, one must not only alleviate the pain, but also address the underlying disease. Pain killers such as Ibuprofen are commonly used and relieve pain, however, they do not prevent the progression of disease. Surgery is often used to restore the function of any damaged organs, removes scarring and adhesions, and alleviate pain. Surgery is very successful in both relieving the symptoms and improving pregnancy rates. Unfortunately, even though the disease is removed, the underlying cause of the disease has not changed and the disease will likely recur over time. Surgery should involve full excision of all endometriosis as well as postoperative medical therapy.

In severe cases of endometriosis, surgeons should be prepared to remove endometriosis from the bowel or bladder. Most women will be able to have a laparoscopic procedure (i.e., a minimally invasive surgery with small instruments placed through incisions that are approximately ½ inch long in 2 to 3 areas of the abdomen). Most women will go home on the same day as the operation and will generally take between 5-7 days to recover.

In rare cases, the disease is so severe that a laparoscopy may not be possible. A full incision called a laparotomy may be required. This operation requires a larger open incision and several nights stay in the hospital as well as a longer recovery time. Unless the disease is very advanced this is unlikely to be necessary. A hysterectomy should be reserved as a last resort in extreme cases and only after a woman has completed her family.

Medical therapy generally involves altering the hormones that cause the growth of the endometrium and spread of these cells within the abdomen. These medications may be used on their own or after surgery to prevent recurrence of the disease. Common therapies include an oral contraceptive pill. The oral contraceptive is the most common treatment used to suppress the period and stop mild to moderate endometriosis from progressing while addressing the pain. The combined oral contraceptive can be given in a fashion that completely eliminates the menses and will therefore eliminate painful periods. In a woman who does not want to conceive, these are highly effective first-line therapies. If oral contraceptives do not work or if there are side effects from these oral contraceptives, often a progestin is given as a second-line therapy. They also inhibit estrogen and the growth of the endometrium. These pills are given orally and often are more effective than oral contraceptives at relieving the symptoms of endometriosis. They may also have more side effects than an oral contraceptive, however less than some other medications. Danizol is a hormone derived from the male hormone testosterone. It also can be very effective at reducing endometriosis. However, because of its male-like hormone, there may be unwanted side effects such as hair growth or acne. Gonadotrophin release hormone agonists are given by injection. These hormones stop the production of estrogen and progestin and are highly effective at relieving endometriosis. After preventing the production of a woman’s own natural reproductive hormones, that woman may experience menopause like symptoms such as hot flushes and night sweats. These should be eliminated by the addition of a progestin. We call this “add-back” therapy. This therapy nearly always eliminates all of the unwanted side effects of the gonadotrophin releasing hormone agonist and has added benefit in that the progestin is an additional agent to treat the endometriosis. The gonadotrophin releasing hormone agonists have been used without ‘add-back’ therapy producing severe unwanted side effects. Current treatments strategies completely avoid these unwanted side effects making medications much more amenable as a reasonable form of endometriosis therapy.

Many alternative therapies such as acupuncture, yoga, massage and relaxation exercises may be of assistance in some women in easing the stress or symptoms of endometriosis. Complimentary (herbal) medications and vitamins have been suggested as possible therapies to help with pain control. None are well tested or proven to be effective and some may interfere with the therapies. You should ask your physician prior to taking complimentary medications and vitamins. Vitamin E, Zinc, and Magnesium have been suggested to be effective in easing menstrual pain and endometriosis pain.
Endometriosis is a chronic condition. There is no permanent cure. Lifestyle alterations are often helpful in relieving the pain and stress of endometriosis. Aerobic exercise has been shown to be effective. Relaxation, a healthy diet and exercise can improve your sense of well-being and help to maintain a positive attitude in addition to helping one cope with the stress of a chronic painful condition.

Additional Questions and Resources

As described above, endometriosis can interfere with fertility in multiple ways. Inflammation, adhesions, cysts and scarring will prevent egg production, the transport of egg to the sperm in the fallopian tube, fertilization and the attachment of the embryo to the uterus. Pregnancy rates are significantly lower in women with endometriosis. Surgical therapy to remove the endometriosis will help to improve pregnancy rates. There are no medications by themselves that will specifically target endometriosis and allow one to conceive. All of the medications listed above will prevent pregnancy. Medications to enhance fertility in general are often enough to overcome the impediments of endometriosis. These include medications to improve the quality and number of eggs produced. If scarring and damage from endometriosis is severe enough in vitro fertilization may be the optimal modality to use in overcoming infertility associated with endometriosis. In vitro fertilization involves directly removing the eggs from the toxic environment of the ovary and pelvic cavity, bypassing the fallopian tubes, growing the embryos outside of the body and replacing embryos into the uterus. IVF achieves the highest success rates in endometriosis related infertility.

Endometriosis is a chronic condition. It can be draining on you, your friends, co-workers and family members. Often women describe a loss of control as endometriosis may disrupt daily activities, and may force time off from work, missing social occasions, or interfering with your ability to interact with family members in a positive way. Chronic pain can lead to sleeplessness and irritability. In addition to the physical discomfort, you may experience one of the following:

  • Stress
  • Anxiety
  • Depression
  • Fatigue
  • Poor body image
  • Lack of self-esteem
  • Loss of sex drive
  • Anger
  • Frustration

Some of these symptoms are a natural result of constant or intermittent pain, and can become overwhelming at times. It is important to keep a positive attitude and be proactive in managing your condition. This is especially important if you are trying to become pregnant. Infertility, even in the absence of pain, can result in many of the same symptoms described above. There are multiple ways to cope with the disease. Most important of course, is being proactive in coming to a diagnosis and getting treatment. The earlier this happens, the more likely the disease will be well controlled and the long term damage will be prevented. Find as much information as possible about endometriosis so you are in a better position to make decisions in the diagnosis and treatment of your disease. Exercise and healthy living will not only help control the pain symptoms, but also help improve your feelings of well being. Be sure to take time out for things that you enjoy doing and prioritize those tasks that are most important. Be sure to know what can be deferred when you are not feeling well, and what things must be a priority when you do feel well. Most importantly, share information about your disease with family members and trusted colleagues. Build a social support network. Think about what tasks or responsibilities may not be necessary or that can be delegated to someone else when needed. Often you will find that friends and family members will rally to your aid when they realize you are affected by a serious medical condition.

If at any stage you feel that you are not adequately coping with the disease, talk to close friends and relatives. Also reach out to your doctor and seek help from a counselor or a psychologist. The physicians at the Yale Fertility Center are there to help and psychological support is also available. There are also professional groups that have information available on endometriosis. These include the Endometriosis Association. The Endometriosis Association can be found at www.endometriosisassn.org.

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New Haven
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New Haven, CT 06511-6110
Tel: 203-785-4708 / 1-877.Yale.IVF

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Westport, CT 06880
Tel: (203) 341-8899 

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Guilford, CT 06437
Tel: (203) 785-4708

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Stamford, CT 06912
Tel: (203) 341-8899 

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