- Adenomyosis is endometrial-like tissue growing within the muscle wall of the uterus; imaging-based studies suggest it affects roughly 20 to 35 percent of reproductive-age women.
- Common symptoms are heavy menstrual bleeding, worsening menstrual cramps, chronic pelvic pain, and painful intercourse, though about a third of women have no symptoms.
- Transvaginal ultrasound and MRI now diagnose it in the clinic, ending the old reliance on hysterectomy specimens.
- First-line medical options include the levonorgestrel IUD, combined oral contraceptives, and progestins such as dienogest; GnRH analogues are typically second-line.
- Hysterectomy is the only definitive cure, but most women get lasting relief from non-surgical care; see a gynecologist and seek emergency care for heavy bleeding with dizziness or fainting.
PASTE BELOW THIS LINE INTO THE WORDPRESS EDITOR
—————————————————————-
Once thought to occur mainly in women in their 40s after multiple pregnancies, adenomyosis is now recognized in younger women, women without children, and increasingly during fertility evaluation. Imaging advances have moved diagnosis out of the operating room and into the clinic. Studies estimate adenomyosis affects somewhere between 20 and 35 percent of reproductive-age women, though many cases go unrecognized because symptoms overlap heavily with endometriosis and fibroids.
Quick summary: Adenomyosis is a benign condition in which uterine-lining tissue grows into the muscle wall of the uterus, often causing heavy periods and pelvic pain. It is diagnosed with transvaginal ultrasound or MRI, and most women improve with medical treatment such as the levonorgestrel IUD before surgery is ever considered. This article is educational and not a substitute for care from a qualified clinician.
What Adenomyosis Is and How Common It Is
Adenomyosis is a condition in which endometrial-like tissue — the glands and stroma that normally line the uterine cavity — grows within the muscle wall (myometrium) of the uterus. This invasion can be diffuse, involving most of the uterine wall, or focal, forming a discrete area sometimes called an adenomyoma. The result is an enlarged, often boggy uterus with disordered muscle architecture.
Estimating prevalence is difficult because diagnosis historically required hysterectomy specimens. Recent imaging-based studies suggest 20 to 35 percent of women may have adenomyosis, with higher rates in those undergoing evaluation for heavy menstrual bleeding, painful periods, infertility, or chronic pelvic pain. According to the Cleveland Clinic, adenomyosis frequently coexists with fibroids and endometriosis, which is one reason it is often overlooked. For broader context on related conditions, see our medical conditions resource.
Causes and Risk Factors
The mechanism is not fully understood, but leading hypotheses include invagination of basal endometrium into the myometrium through a disrupted junctional zone, and metaplasia of embryonic remnants within the uterine wall. Estrogen and progesterone receptor signaling, inflammation, and altered local immunity all appear to contribute.
Risk factors include increasing age (peak diagnosis in the late 30s and 40s, though this may reflect detection bias), prior uterine surgery (cesarean delivery, dilation and curettage, myomectomy), multiparity, tamoxifen use, and possibly conditions associated with chronic uterine inflammation. The American College of Obstetricians and Gynecologists recognizes adenomyosis as a leading cause of secondary dysmenorrhea. Because the evidence base is still evolving, these are associations rather than proven causes, and having a risk factor does not mean you will develop the condition.
Symptoms
About a third of women with adenomyosis are asymptomatic. When symptoms occur, the most common are heavy menstrual bleeding (in roughly 40 to 60 percent of cases), severe menstrual cramps that may worsen progressively, chronic pelvic pain between periods, dyspareunia (pain with intercourse), and a sensation of uterine enlargement or fullness.
Adenomyosis is increasingly implicated in subfertility and pregnancy complications, including reduced implantation rates after IVF, increased miscarriage, and obstetric outcomes such as preterm birth and preeclampsia, according to published reviews in the fertility literature. The pain pattern often differs from endometriosis: deeper, more uterine-centered, and tightly linked to menstruation. Symptoms vary widely from person to person, so the only reliable way to sort out the cause is a clinical evaluation.
How Adenomyosis Is Diagnosed
Diagnosis once relied on histology after hysterectomy, but transvaginal ultrasound and MRI now permit reliable diagnosis in most cases. Ultrasound features include a globular or asymmetrically thickened uterus, myometrial cysts, heterogeneous myometrial echotexture, and the so-called “venetian blind” shadowing pattern. Skilled sonographers achieve sensitivity and specificity above 80 percent, though accuracy depends heavily on operator experience.
MRI is more reproducible and shows thickening of the junctional zone (greater than 12 mm is highly suggestive) and high-signal foci within the myometrium. The Morphological Uterus Sonographic Assessment (MUSA) consensus criteria, published in Ultrasound in Obstetrics and Gynecology, standardize the ultrasound features used in modern diagnosis. Endometrial biopsy is sometimes obtained to evaluate concurrent abnormal bleeding but does not diagnose adenomyosis itself. If you have symptoms, ask whether a clinician experienced in gynecologic imaging is available, since detection rates rise substantially with expertise.
Treatment Options
Treatment is symptom-driven and depends on age, fertility goals, and disease pattern. There is no single best treatment for everyone, and current guidance from bodies such as the Society of Obstetricians and Gynaecologists of Canada (Guideline No. 437, 2023) emphasizes tailoring therapy to the dominant problem — heavy bleeding, pain, or infertility. Medical management is usually first-line.
NSAIDs and tranexamic acid help mild dysmenorrhea and bleeding. First-line hormonal options include the levonorgestrel-releasing IUD, combined oral contraceptives, and progestins such as dienogest. The levonorgestrel IUD has the strongest evidence and reduces bleeding and pain in a large majority of women in published series. Choice among these depends on side-effect tolerance, contraceptive needs, and whether pregnancy is desired.
GnRH agonists and the newer GnRH antagonists (relugolix combination, elagolix combination) are effective but are generally used as second-line agents; when GnRH agonists are used for longer than about six months, add-back hormone therapy is recommended to protect bone and control menopausal side effects. In severe cases, some specialists use a two-step strategy: a GnRH antagonist to rapidly quiet the disease, followed by a maintenance option such as the levonorgestrel IUD or a progestin. Aromatase inhibitors and danazol have been used in selected cases. Any hormonal regimen should be individualized with a clinician rather than self-started.
Procedural options include uterine artery embolization, which reduces symptoms in many women but has uncertain effects on fertility, and MRI-guided focused ultrasound for focal disease. Endometrial ablation may help bleeding in carefully selected patients. Surgical removal of a focal adenomyoma is technically challenging and typically only considered for fertility preservation in selected cases. Hysterectomy is the only definitive cure and remains the most common surgical option for women with severe symptoms who have completed childbearing.
Treatment at a Glance
| Goal | Commonly considered options |
|---|---|
| Reduce heavy bleeding | Levonorgestrel IUD, tranexamic acid, combined pills, dienogest, ablation |
| Control pain | NSAIDs, levonorgestrel IUD, combined pills, GnRH analogues (second-line) |
| Preserve fertility | Individualized medical therapy, focal adenomyomectomy in selected cases |
| Definitive cure | Hysterectomy (after childbearing is complete) |
This table is a general overview, not a treatment plan; the right choice depends on your symptoms, imaging, and goals, and should be decided with your clinician.
When to See a Doctor
Schedule a visit if you have heavy or prolonged menstrual bleeding, severe menstrual cramps unresponsive to NSAIDs and hormonal contraception, pain during intercourse, chronic pelvic pain, or difficulty conceiving. New onset of severe dysmenorrhea after age 30 — secondary dysmenorrhea — is particularly suggestive of adenomyosis, fibroids, or endometriosis and warrants evaluation.
If you have known adenomyosis and pain or bleeding worsens despite treatment, follow-up is warranted. New symptoms in postmenopausal women, including any vaginal bleeding, require evaluation regardless of prior diagnosis.
When to seek emergency care: Call 911 or go to the nearest emergency room if you experience heavy vaginal bleeding causing dizziness, weakness, or fainting; sudden severe pelvic pain; signs of severe anemia such as chest pain or shortness of breath; or fever with pelvic pain that may indicate infection.
Frequently Asked Questions
How is adenomyosis different from endometriosis?
Both involve endometrial-like tissue in abnormal locations. Endometriosis deposits grow outside the uterus; adenomyosis deposits are within the muscle wall of the uterus itself. The conditions often coexist and share many symptoms, but treatment strategies differ.
Can adenomyosis cause infertility?
It is associated with reduced implantation, increased miscarriage, and poorer IVF outcomes in some studies, though not every woman with adenomyosis has trouble conceiving. Treatment with the levonorgestrel IUD or GnRH agonist pretreatment before fertility cycles may improve outcomes in selected patients. See our female infertility guide and discuss options with a fertility specialist.
Does adenomyosis go away after menopause?
Symptoms typically improve after menopause as estrogen declines. Adenomyosis may persist or recur in women on systemic hormone therapy. New postmenopausal symptoms warrant evaluation.
Is hysterectomy the only cure?
Hysterectomy is the only definitive cure, but many women achieve good symptom control with medical management — particularly the levonorgestrel IUD, progestins, or GnRH antagonist combinations — for years before considering surgery. The decision depends on symptom severity, fertility goals, and personal preference.
Is adenomyosis a form of cancer?
No. Adenomyosis is a benign (non-cancerous) condition. It does not turn into cancer, though it can cause significant symptoms. Any unusual bleeding, especially after menopause, should still be evaluated to rule out other causes.
The Bottom Line
Adenomyosis is more common than once thought and now diagnosable in the office through high-quality imaging. Most women have effective non-surgical options, especially the levonorgestrel-releasing IUD, progestins, and the newer GnRH antagonist combinations. For women with completed childbearing and severe symptoms, hysterectomy provides definitive relief. A gynecologist familiar with modern adenomyosis management can help match treatment to your symptoms and life stage. Use this guide to prepare questions for that visit rather than as a replacement for personalized medical advice.