What is the normal thickness of the endometrium during menstruation?

The thickness of the endometrium during menstruation is usually 1-4 mm, and the specific thickness is related to the stage of the menstrual cycle.

Endometrial thickness changes dynamically with the menstrual cycle. During the menstrual period, due to the decrease in hormone levels, the functional layer of the endometrium sheds to form menstrual blood. At this time, ultrasound examination shows that the endometrium is the thinnest, usually 1-4 mm. During the proliferative phase, with the development of follicles and the action of estrogen, the intima gradually thickens to 5-7 mm. After ovulation, the secretory phase enters, and the endometrium further thickens to 7-14 mm under the action of progesterone to prepare for the implantation of the fertilized egg. If pregnancy does not occur, the corpus luteum atrophies, causing hormone levels to drop, and the endometrium sheds again into the next menstrual cycle. To measure the thickness of the endometrium, a vaginal ultrasound examination must be performed within 3 days after menstruation, when the basal layer is clearly visible. Abnormal thickening may indicate endometrial polyps, endometrial hyperplasia and other lesions, and pathological examination is required for diagnosis.

It is recommended that women undergo regular gynecological examinations and pay attention to changes in their menstrual cycles. Maintain a regular daily schedule, avoid excessive dieting or obesity, and moderate exercise can help maintain endocrine balance. If symptoms such as abnormal menstrual flow, prolonged menstruation, or non-menstrual bleeding occur, you should seek medical attention promptly to evaluate the condition of the endometrium. Women over 40 years old can undergo gynecological ultrasound screening once a year, and those with high-risk factors for endometrial cancer need to strengthen monitoring.