Adenomyosis and Fertility: What It Is, How It's Diagnosed, and What to Do About It
Adenomyosis explained — what it is, how it differs from endometriosis, its impact on fertility, and how it's managed when you want to conceive.
Adenomyosis is frequently mistaken for endometriosis — or dismissed as "just bad periods" — for years before it's correctly named. For fertility, naming it correctly matters, because the treatment implications are specific. Here's what it is and what it means if you're trying to conceive.
What is adenomyosis?
Adenomyosis occurs when endometrial tissue — the same tissue that normally lines the inside of the uterus — grows into the uterine muscle wall itself. This is a distinct process from what happens in the uterine cavity normally, and the tissue embedded in the muscle behaves like uterine lining does: it responds to hormones and bleeds. Over time, this creates a thickened, enlarged, often painful uterus.
What are the symptoms of adenomyosis?
The classic presentation includes heavy menstrual bleeding, severe period pain, and a feeling of pelvic pressure or fullness. On physical exam, the uterus often feels enlarged or "bulky." Many people carry an adenomyosis diagnosis for years without knowing it because the symptoms overlap significantly with fibroids, endometriosis, and what gets categorized as "just bad periods." Heavy, painful cycles warrant imaging — not reassurance that they're normal.
What is the difference between adenomyosis and endometriosis?
The tissue type is similar — both involve endometrial-like tissue growing where it shouldn't — but the location is different. In endometriosis, that tissue grows outside the uterus entirely: on the ovaries, fallopian tubes, bowel, bladder, or elsewhere in the pelvis. In adenomyosis, the tissue grows into the uterine muscle wall. They are separate conditions that often coexist, and the presence of one does not confirm or rule out the other.
How is adenomyosis diagnosed?
Transvaginal ultrasound can suggest adenomyosis based on characteristic changes in the uterine muscle texture; MRI provides more definitive imaging when the diagnosis is uncertain. Historically, definitive diagnosis required examining a hysterectomy specimen, but imaging is now generally sufficient for fertility planning and treatment decisions. If your ultrasound report notes myometrial heterogeneity, asymmetry, or features suggestive of adenomyosis, ask your provider to discuss the implications directly.
Can you get pregnant with adenomyosis?
Yes — adenomyosis is not an absolute barrier to pregnancy. Many people with adenomyosis conceive naturally or through treatment. That said, it often coexists with endometriosis or fibroids, which compounds the impact. Once pregnant, adenomyosis is associated with higher risks of preterm birth, preeclampsia, and placental complications, which means pregnancy will be managed as higher-risk. Your OB should know the diagnosis going in — that's appropriate planning, not cause for alarm.
How does adenomyosis affect fertility?
Adenomyosis can impair implantation and is associated with higher miscarriage rates and lower IVF success rates per embryo transfer. The mechanism is thought to involve altered uterine contractility and changes in the endometrial environment that make it less receptive to an implanting embryo. The impact varies — diffuse, extensive adenomyosis tends to have a greater effect than focal or mild forms.
Does adenomyosis affect IVF success rates?
Yes — per-transfer success rates in IVF are lower in the presence of adenomyosis compared to uteri without the condition. The difference is meaningful enough that fertility specialists should account for it in prognosis discussions. GnRH agonist suppression (a medication that temporarily suppresses estrogen) for 2–3 months before an embryo transfer improves IVF outcomes in adenomyosis and is standard of care in many programs. If you have adenomyosis and are planning an embryo transfer, ask whether pre-transfer suppression has been considered.