Adenomyosis vs. Uterine Fibroids

Adenomyosis vs. Uterine Fibroids: What's the Difference?

Illustration of uterus with fibroids.
Uterine fibroids are tumors -- usually benign -- in the wall of the uterus.

Uterine adenomyosis is a condition in which the inner lining of the uterus grows into the muscle wall of the uterus (myometrium) causing heavy, painful menstrual periods. Adenomyosis often seen with other uterine problems such as endometriosis. Endometriosis is a condition in which endometrial cells (the lining of the uterus) grow outside of the uterus.

Uterine fibroids are muscular tumors that grow in the wall of the uterus (womb). Fibroids are almost always benign (not cancerous). Not all women with fibroids have symptoms. Women who do have symptoms often find fibroids hard to live with. Some have pain and heavy menstrual bleeding. Treatment for uterine fibroids depends on your symptoms.

What Are the Symptoms of Adenomyosis and Uterine Fibroids?

Often uterine fibroids do not cause any symptoms. Symptoms of adenomyosis and uterine fibroids that are similar include heavy menstrual periods (which can be so heavy they lead to anemia), painful periods/menstrual cramping, lower abdominal pain or tenderness, back pain, feeling of fullness or pressure in the pelvic area, abdominal bloating/swelling, pain during intercourse,

Symptoms of adenomyosis that are different from uterine fibroids include prolonged menstrual bleeding, chronic pelvic pain, leg pain, and blood clots in the pelvis and legs.

When symptoms of uterine fibroids occur, those that are different from adenomyosis include frequent urination, pregnancy and labor complications (including a greater risk of needing cesarean section, and infertility (rare).

How Are Adenomyosis and Uterine Fibroids Diagnosed?

Along with a medical history and pelvic examination, diagnoses of adenomyosis or uterine fibroids are made through imaging such as ultrasound and magnetic resonance imaging (MRI). X-rays and cat scans (CT scan) may be done to confirm fibroids.

The only true diagnosis of adenomyosis can be made based on pathology of the uterus which is evaluated after a hysterectomy (removal of the uterus).

In some cases, a surgical procedure such as a laparoscopy or hysteroscopy may be performed to view the uterus and other organs to confirm or rule out the presence of fibroids.

What Is the Treatment for Adenomyosis and Uterine Fibroids?

The only cure for adenomyosis is surgical removal of the uterus called a hysterectomy. Treatment options for adenomyosis that may reduce heavy bleeding include intrauterine devices (IUDs), specifically one which releases the hormone progestin, endometrial ablation, and uterine artery embolization. Treatments for adenomyosis pain include birth control pills, over-the-counter (OTC) pain medications such ibuprofen (Advil and Motrin) or naproxen (Aleve), and the prescription medication leuprolide (Lupron, Eligard).

Most women with fibroids do not have any symptoms and treatment is not needed. Treatment for fibroids may include over-the-counter (OTC) pain medications such ibuprofen (Advil and Motrin) or naproxen (Aleve), iron supplementation for heavy bleeding to prevent anemia, birth control pills to control heavy bleeding, and the prescription medication leuprolide (Lupron, Eligard). Severe fibroids may require surgery, which can be either a myomectomy to remove the fibroids while leaving healthy tissue intact, or hysterectomy, which is removal of the uterus. Other surgical procedures include endometrial ablation which removes the lining of the uterus to control heavy bleeding, myolysis which uses electric current or freezing to destroy the fibroids, and uterine fibroid embolization (UFE), or uterine artery embolization (UAE) which are procedures used to block the blood supply to the fibroids, causing them to shrink.

A hysterectomy to remove the uterus will cure adenomyosis and women will have no further symptoms.

Women with adenomyosis may be at higher risk of developing endometrial and thyroid cancers. Fibroids are almost always benign and not cancerous). In rare cases a cancerous fibroid can occur (leiomyosarcoma).

What Is the Prognosis for Adenomyosis and Uterine Fibroids?

Adenomyosis

  • A hysterectomy to remove the uterus will cure adenomyosis, and women will have no further symptoms.
  • Women with adenomyosis may be at higher risk of developing endometrial and thyroid cancers.
  • In women who do not have a hysterectomy, it is not clear whether adenomyosis affects fertility. Some studies show it decreases fertility and other studies show it has no effect on getting pregnant. It is believed the severe inflammation caused by adenomyosis may inhibit implantation of an embryo into the uterine lining, preventing pregnancy from occurring.

Uterine Fibroids

  • Treatment success and future outcome depend on the severity of the fibroid or fibroids prior to treatment and the chosen treatment.
  • Fibroids may affect fertility, but this depends on the size and location of the fibroids.
  • Many women with fibroids are older than 35 years. This and other factors such as decreased egg quality and decreased ovulation contribute to their inability to become pregnant.
  • Fibroids rarely turn into cancer. This is more likely to occur in women after menopause.
  • The most common warning sign of cancer is a rapidly growing tumor that requires surgery.

What Is the Prognosis for Adenomyosis and Uterine Fibroids?

Adenomyosis

  • A hysterectomy to remove the uterus will cure adenomyosis, and women will have no further symptoms.
  • Women with adenomyosis may be at higher risk of developing endometrial and thyroid cancers.
  • In women who do not have a hysterectomy, it is not clear whether adenomyosis affects fertility. Some studies show it decreases fertility and other studies show it has no effect on getting pregnant. It is believed the severe inflammation caused by adenomyosis may inhibit implantation of an embryo into the uterine lining, preventing pregnancy from occurring.

Uterine Fibroids

  • Treatment success and future outcome depend on the severity of the fibroid or fibroids prior to treatment and the chosen treatment.
  • Fibroids may affect fertility, but this depends on the size and location of the fibroids.
  • Many women with fibroids are older than 35 years. This and other factors such as decreased egg quality and decreased ovulation contribute to their inability to become pregnant.
  • Fibroids rarely turn into cancer. This is more likely to occur in women after menopause.
  • The most common warning sign of cancer is a rapidly growing tumor that requires surgery.
References
Center for Innovative GYN Care. Adenomyosis. 2019. 6 January 2020. .

Office on Women’s Health. Uterine fibroids. 1 April 2019. 4 February 2020. .

The doctors and editors at UpToDate. Patient education: Uterine adenomyosis (The Basics). 2020. 6 January 2020. .

Yeh, Chih-Ching, et al. Women with adenomyosis are at higher risks of endometrial and thyroid cancers: A population-based historical cohort study. 9 March 2018. January6 2020. .