Endometrial Thickness Guidelines

Postmenopausal Women

The American College of Radiology recommends that an endometrial thickness of ≤4 mm in postmenopausal women effectively excludes endometrial malignancy and requires no further evaluation if the patient is asymptomatic 1, 2
The American College of Radiology suggests that when endometrial thickness measures ≥5 mm in postmenopausal women, endometrial tissue sampling is generally warranted 1, 2
The European Society for Medical Oncology uses a slightly more conservative cut-off of 3-4 mm for postmenopausal women 3, 2
Transvaginal ultrasound (TVUS) is the first-line screening test for evaluating endometrial thickness in postmenopausal women, particularly those with bleeding, as recommended by the American College of Radiology 1, 2
The American College of Radiology recommends combining TVUS with transabdominal ultrasound for complete pelvic assessment in postmenopausal women 1, 2

The American College of Radiology states that endometrial thickness measurement has limited diagnostic value in premenopausal women and should not be used to exclude pathology 1
Clinical symptoms, such as abnormal uterine bleeding, rather than thickness measurements, should guide the decision for endometrial sampling in premenopausal women, according to the American College of Radiology 1
Even if endometrial thickness is <5 mm in premenopausal women, endometrial polyps or other pathology may still be present, as noted by the American College of Radiology 1

In early pregnancy evaluation, an endometrial thickness <8 mm virtually excludes normal intrauterine pregnancy, as reported by the American College of Radiology 5
An endometrial thickness of ≥25 mm virtually excludes ectopic pregnancy, according to the American College of Radiology 5