Endometriosis
A 30-year-old woman has been unable to conceive for six years despite regular unprotected intercourse. She has severe cramping pelvic pain beginning two days before each period, no longer relieved by naproxen, with deep dyspareunia and pain on defecation during menstruation. Cycles are regular at 29 days. Bimanual examination reveals a fixed retroverted uterus and tender nodularity along the uterosacral ligaments. Which of the following is the most likely diagnosis?
- A.Uterine leiomyomata
- B.EndometriosisCorrect
- C.Chronic endometritis
- D.Pelvic congestion syndrome
Explanation
The triad of progressive secondary dysmenorrhoea refractory to non-steroidal anti-inflammatory drugs, deep dyspareunia, and subfertility is the classic presentation of endometriosis. Ectopic endometrial tissue responds to cyclical hormones, bleeds into the peritoneum, and provokes inflammation, adhesions, and eventually a frozen pelvis, which explains the fixed retroverted uterus and tender uterosacral nodules found on examination. Infertility arises through distorted pelvic anatomy, impaired tubal function, an inflammatory peritoneal environment toxic to gametes, and reduced ovarian reserve when endometriomas are present. Dyschezia during menstruation suggests rectovaginal or uterosacral deposits. Leiomyomata typically cause heavy menstrual bleeding with a bulky irregular but mobile uterus rather than a fixed one, and dyspareunia and dyschezia are unusual. Chronic endometritis follows instrumentation or pelvic infection and presents with abnormal bleeding and pelvic pain that is not strictly cyclical, without uterosacral nodularity. Pelvic congestion syndrome causes a dull ache worse on prolonged standing and after intercourse rather than crescendo perimenstrual pain, and it does not fix the uterus. Transvaginal ultrasound is the first-line imaging test and detects endometriomas and deep infiltrating disease, but laparoscopy with histology remains the definitive diagnosis; treatment should not be delayed for it.
Why each option
- A.
- Fibroids cause heavy bleeding and a bulky but mobile uterus, and rarely explain severe cyclical pain with uterosacral nodules.
- B.
- Correct. Refractory secondary dysmenorrhoea with deep dyspareunia, infertility, a fixed uterus, and uterosacral nodularity is diagnostic until proven otherwise.
- C.
- Endometritis produces non-cyclical pain and abnormal bleeding, usually after instrumentation or infection, without a fixed retroverted uterus.
- D.
- Pelvic congestion causes a positional dull ache worse on standing rather than crescendo perimenstrual pain, and does not fix the pelvic organs.
Reference: ESHRE Guideline on Endometriosis, 2022
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