What is the normal thickness of the endometrium?

The normal thickness of the endometrium varies during different phases of the menstrual cycle, but generally fluctuates between 1-10 mm.

The proliferation phase is from the 5th to the 14th day of the menstrual cycle. During this stage, the endometrium gradually thickens under the action of estrogen, from 0.5mm to about 3-5mm. The secretory phase is from the 15th to the 28th day of the menstrual cycle, also known as the luteal phase. During this phase, the endometrium further thickens and becomes soft, containing rich nutrient tissue, which is conducive to the implantation and development of the fertilized egg. In the late secretory phase, the thickness of the endometrium can reach about 10mm. The menstrual phase is from the 1st to the 5th day of the menstrual cycle. With the rapid decline of estrogen and progesterone, the corpus luteum shrinks, the endometrium begins to exfoliate, and the thickness rapidly decreases from 10mm to about 3-5mm.

To summarize the normal range, the endometrial thickness is usually between 3-5mm in the early menstrual period; the endometrial thickness is between 5-10mm in the mid-menstrual period, and can reach 10mm in the late secretory period; the endometrium begins to exfoliate and the thickness rapidly decreases to 3-5mm.

Too thin or too thick endometrium may affect women's reproductive function. Too thin endometrium may lead to scanty menstruation or amenorrhea, while too thick endometrium may lead to heavy bleeding and endocrine disorders. If abnormal endometrial thickness is found, it is recommended to seek medical attention in time for relevant examinations and treatment.