When Good Glands Go Bad


Similarities and Differences Between Endometriosis and Adenomyosis

There is much confusion between two conditions—endometriosis and adenomyosis—and this is because they are similar in how they develop. The innermost lining of your uterus (womb), that lining that discards itself and then renews itself with each monthly cycle in preparation for pregnancy, is the origin of gland-like cells that can cause problems when they exist anywhere but in this innermost lining. 

Called the endometrium, this lining is designed to fall away as the debris you normally see as your “period,” made up of bloody, deteriorated glandular elements. When they are present anywhere else, they are technically “invaders,” and they don’t play well with other tissue; this is because there is no escape like there is normally through the vagina onto a tampon or pad. These glandular tissues are hormonally responsive, and when the menstrual cycle continues, such persistent “outposts” are sites of severe inflammation that cause pain and abnormal function in these unusual locations.

What a Difference a Word Makes!

The words endometriosis and adenomyosis have different origins

  • Endometriosis, translated, means “a condition of endometrium-like tissue outside of your uterus”; whereas 
  • adenomyosis means this endometrial tissue does not limit itself to the innermost lining of your uterus, but invades into the thick, permanent muscular part of the wall (the next—middle—layer).

As such, endometriosis is endometrium-like tissue in places outside your uterus, while adenomyosis is actual endometrial tissue invading deeper into your womb (doesn’t limit itself to the lining that falls away each period). 

While it is tempting to think of adenomyosis as endometriosis of your uterus—and some websites say this—this really highlights a basic misunderstanding between the two. Below are reasons why this notion is too simplistic at best and just plain wrong at worst.

Endometriosis: Glandular Invasion Outside of Your Uterus

Exactly how endometriosis travels and attaches to tissues/organs outside of your uterus has been the subject of much debate. 

  • Retrograde Menstruation: the most logical explanation is the one provided by the “retrograde menstruation” theory. Normally the endometrium loosens and falls away into the inside of your uterus when the normally fluctuating and cycling hormones of your cycle are at their lowest. And again, normally, its exit is naturally through your cervix, then vagina, and then to the outside world for discarding as part of typical menstrual hygeine. 

But there is also a direct route into the opposite direction—through your tubes that empty into your pelvis, which allows this bloody and glandular debris to drip onto your tubes, ovaries, bladder, rectum, and even intestines. Not being discarded is the problem, where this tissue persists to cause inflammation and provoke a serious immunological reaction that results in pain and infertility. 

  • Vascular/Lymphatic Spread: another theory suggests that glandular cells from the endometrium can get caught up in the blood or lymphatic vessels and be carried to sites away your uterus. This would explain how endometriosis can be found in some women in the nose (monthly nosebleeds), the lungs (monthly coughing up blood), or even the brain (monthly ministrokes). 
  • Congenital: a third explanation is that reproductive tissue that normally migrates to the pelvis during development of the embryo may leave a trail of such tissue along this “migration” route, resulting in nests of endometrial-like tissue throughout the body that persist after birth and into adulthood. 

Adenomyosis: Glandular Invasion into Your Uterus

Adenomyosis is when endometrial tissue (not endometrial-like, but actual endometrial glandular cells) invade the layer that overlies that innermost endometrium layer. That overlying layer is the permanent muscular portion of your uterus, and its confinement to your uterus makes it different from endometriosis. But like endometriosis, these glandular tissues—being in the wrong place—are a site of inflammation, immunological reaction, and therefore pain.

What’s Worse? Endometriosis or Adenomyosis?

Both can be painful, but endometriosis is more likely to cause infertility by two mechanisms:

  1. Causing scarring amid the ovaries and tubes, blocking the descent of an egg for fertilization or the swimming up of sperm to fertilize the egg.
  2. Provoking an inflammation that makes for bad chemistry, causing dysfunction in ovulation and fertilization itself.

How are the Signs and Symptoms of Endometriosis and Adenomyosis Similar and Different?

Similarities: both cause pain, especially during menstruation.

Differences: the menstrual pain of adenomyosis is usually confined to your uterus—in the central pelvis and possibly radiating to your lower back and inguinal areas; however, endometriosis pain causes mild-to-severe discomfort in any areas where the endometriosis is planted. This can mean in the rectum with bowel movements, the bladder with urination or bladder-filling, or on one or both sides if the tube(s) and/or ovaries are involved. (One particular condition, an “endometrioma,” is a cyst in the ovary filled with endometriosius; it is referred to as a “chocolate cyst.”)

Can You Have Both Endometriosis AND Adenomyosis?

Yes, but his is somewhat unusual, as the two conditions are more common in different populations:

  • Adenomyosis occurs more frequently in women who have had prior pregnancy or pregnancies, so therefore older than the women who have endometriosis (late twenties to forties). 
  • Endometriosis, because of its relationship with infertility, occurs in women who typically have had no children yet, and therefore this is a younger population (puberty to twenties). 

How are Endometriosis and Adenomyosis Diagnosed?

Unfortunately, both are considered surgical diagnoses.

  • An official diagnosis of adenomyosis is made under the microscope of tissue from the uterus that has been removed via hysterectomy.

    Because of this very final method of diagnosis, it is seldom diagnosed in a woman who still desires more children (that is, the use of her uterus!). But it can be guessed at with increased suspicion when a woman complains of painful periods, painful intercourse, and—most telling—her doctor’s exam which reveals her uterus to be slightly enlarged and “boggy,” that is, not the firm consistency of the usual healthy uterus.

  • To make an official diagnosis of endometriosis, the abnormal tissue has to be seen during an exploration into the pelvis and ideally biopsied so that a microscope diagnosis can make it official. Thankfully, robotic techniques, like those performed by Dr. Bozdogan of NYCEndometriosis, have made such procedures same-day and easy to recover from, while also offering actual removal of the endometriosis during the same surgery used for the diagnosis (which saves a woman additional surgery). 

How are Endometriosis and Adenomyosis Treated

Adenomyosis is a problem with the anatomy, so definitive treatment is via hysterectomy. That being said, there is no danger in avoiding this final solution altogether if you are willing to treat the discomfort conservatively with pain medication (usually non-steroidal anti-inflammatories, or NSAIDs) or hormonally (to suppress the period altogether). This is especially important if you desire pregnancy. The connection between adenomyosis and infertility is very vague at best, and many women with adenomyosis are able to successfully get pregnant and deliver normally. 

Endometriosis may be successfully treated with removal of the sites of its implantation. At the same time, the scarring that has resulted can be freed up to improve the chance for fertility. 


Both adenomyosis and endometriosis involve glandular cells that are abnormally present in areas other than the endometrium. Each have similar as well as different symptoms, and each have definitive diagnosis via surgery. Today’s adenomyosis and endometriosis specialists, however, are able to give help toward a normal quality of life and even pregnancy while avoiding surgeries which can deny a woman these things.

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