Adenomyosis refers to endometrial tissue inside the myometrium (muscle layer of the uterus). It is more common in later reproductive years and those that have had several pregnancies (multiparous). It occurs in around 10% of women overall. It may occur alone, or alongside endometriosis or fibroids. The cause is not fully understood, and multiple factors are involved, including sex hormones, trauma and inflammation. The condition is hormone-dependent, and symptoms tend to resolve after menopause, similarly to endometriosis and fibroids.
Adenomyosis typically presents with:
- Painful periods (dysmenorrhoea)
- Heavy periods (menorrhagia)
- Pain during intercourse (dyspareunia)
It may also present with infertility or pregnancy-related complications. Around a third of patients are asymptomatic.
Examination can demonstrate an enlarged and tender uterus. It will feel more soft than a uterus containing fibroids.
Transvaginal ultrasound of the pelvis is the first-line investigation for suspected adenomyosis.
MRI and transabdominal ultrasound are alternative investigations where transvaginal ultrasound is not suitable.
The gold standard is to perform a histological examination of the uterus after a hysterectomy. However, this is not usually a suitable way of establishing the diagnosis for obvious reasons.
Management of adenomyosis will depend on symptoms, age and plans for pregnancy. NICE recommend the same treatment for adenomyosis as for heavy menstrual bleeding.
When the woman does not want contraception; treatment can be used during menstruation for symptomatic relief, with:
- Tranexamic acid when there is no associated pain (antifibrinolytic – reduces bleeding)
- Mefenamic acid when there is associated pain (NSAID – reduces bleeding and pain)
Management when contraception is wanted or acceptable:
- Mirena coil (first line)
- Combined oral contraceptive pill
- Cyclical oral progestogens
Progesterone only medications such as the pill, implant or depot injection may also be helpful.
Other options are that may be considered by a specialist include:
- GnRH analogues to induce a menopause-like state
- Endometrial ablation
- Uterine artery embolisation
Pregnancy and Adenomyosis
Adenomyosis is associated with:
- Preterm birth
- Small for gestational age
- Preterm premature rupture of membranes
- Need for caesarean section
- Postpartum haemorrhage
Last updated June 2020