Irregular Uterine Endometrium
Irregular uterine endometrium refers to an abnormal appearance or uneven thickness of the lining of the uterus (the endometrium) seen on imaging. This finding can be caused by normal hormonal variation, polyps, fibroids, inflammation, or conditions such as endometrial hyperplasia. In some cases, an irregular endometrium may raise concern for precancerous changes or endometrial cancer, especially in postmenopausal individuals. Many cases require follow-up imaging or evaluation to determine the underlying cause.
What is it?
The endometrium normally changes in thickness and appearance throughout the menstrual cycle. When imaging shows thickening, irregular borders, or areas that appear uneven, it may indicate the presence of polyps, small fibroids, inflammation, or hormonal imbalance. In individuals who are postmenopausal, irregular endometrium is less likely to be normal and usually warrants further evaluation.
Ultrasound is the most common test to assess the uterine lining. If the appearance remains unclear, saline sonohysterography can outline the endometrial cavity more clearly, and MRI can offer additional detail. When cancer or precancerous changes are a concern, biopsy is required for diagnosis.
Important to Know
An irregular endometrium is a descriptive finding—not a diagnosis. Many underlying causes are benign, especially in premenopausal individuals. However, postmenopausal bleeding or markedly thickened endometrium may require prompt evaluation to rule out hyperplasia or cancer.
Red flag symptoms include postmenopausal bleeding, very heavy or prolonged periods, bleeding between cycles, pelvic pain, or unexplained fatigue. These symptoms may suggest the need for urgent assessment. Follow-up imaging or biopsy helps determine the cause and guide treatment.