Endometrial thickness of 7mm is normal. Normally, the endometrium can be divided into three phases: early proliferative phase, late proliferative phase and luteal phase. The early stage of endometrial proliferation refers to the period from day 6-11, when the thickness of the endometrium should be in the range of 4-9 mm. The late stage of endometrial proliferation refers to the period from day 11 to follicular ovulation, which is called the late stage of endometrial proliferation, when the thickness of the endometrium is between 9-12 mm. The luteal phase is from the time of ovulation to the time of menstruation, the thickness of the endometrium is between 10-14mm, so the current endometrial thickness of 7mm is normal.