This leaflet is to help you understand what adenomyosis is, what tests you need, and the implication of being diagnosed for you and your baby.

What is adenomyosis?

Normally, the wall of the uterus is made of muscle tissue (called myometrium), while the cavity within the uterus is covered by glandular tissue (called endometrium). Sometimes, some endometrium ends up within the myometrium: this is called adenomyosis. So, adenomyosis is the aberrant presence of glandular tissue belonging to the cavity lining within the wall of the uterus.

How does an adenomyosis happen?

It is not yet fully understood how adenomyosis occurs. The border between the endometrium and the myometrium is called the junctional zone. It is thought that, for one reason or another, glandular tissue covering the cavity of the uterus crosses the junctional zone and settles within the uterine wall. Amidst the myometrium endometriosis is the abnormal presence of endometrium outside the uterus. Occasionally, adenomyosis might arise from endometriosis lesions. In those cases, the glandular tissue invades the myometrium from outside the uterus.

What are the consequences of adenomyosis?

Adenomyosis is a benign condition. Some women with adenomyosis do not report any complaint. Others complain of pain (e.g., during the menstruation or during sexual intercourse) and/or abnormal bleeding (e.g. heavy bleeding during menstruation or bleeding occurring between menstrual periods). Adenomyosis may also interfere with fertility. 

How do I know I have adenomyosis?

Imaging modalities to detect adenomyosis are ultrasonography and magnetic resonance imaging (MRI).  Nowadays ultrasound scan is the first test used because it is well tolerated, available and affordable. However, no test is 100% accurate. This means that a lesion may be missed. This may be because the lesion is small or because the image quality is low (e.g. due to scar tissue after a previous operation or because of shadow caused by bowel content). This also means that the doctor might wrongly think there is adenomyosis. This might be because another lesions (e.g. a fibroid) mimics an adenomyosis lesion or because of suboptimal image quality. 

Should adenomyosis be treated?
If there are no complaints, treatment may not be indicated. The primary treatment of adenomyosis is hormonal: e.g. a contraceptive pill, a progesterone only pill, or a hormonal intrauterine device. In very selected cases surgery might be considered.

What is the spontaneous evolution of adenomyosis?

The spontaneous evolution is highly variable: some lesions remain stable while others expand. After menopause, the adenomyosis tends to diminish and may eventually disappear.

What other questions should I ask?

  • Is adenomyosis a plausible explanation for my complaints?
  • Should my adenomyosis be treated?
  • Is surgery an option?
  • Can I become pregnant if I have adenomyosis?
  • Is there a problem if I become pregnant?
  • Does this mean that also I have endometriosis?


Last updated December 2022