Whether the endometrial thickness of 1.4 cm is normal or not is determined by the specific physiological cycle of the person being measured. If the test is performed before the onset of menstruation, the measurement is normal; if the test is performed just after menstruation or during menopause, the measurement is abnormal. 1. Normal: If the endometrial thickness is measured before the onset of menstruation, the endometrial lining of the uterus is relatively thicker due to the estrogen level in the body. At this time, if the endometrial thickness of 1.4 centimeters is detected, it is still within the normal range and generally does not require special treatment. However, if necessary, another measurement can be taken at the end of menstruation to see if it is within the normal range. 2. Abnormal situation: If the endometrial thickness is 1.4 cm at the end of menstruation or during menopause, it is abnormal. In general, when menstruation has just ended, the thickness of the endometrium is relatively thin, and the normal value is about 0.3~0.5 centimeters. During menopause, the thickness of the endometrium is often less than 0.5 centimeters. If the endometrial thickness of 1.4 centimeters is measured during menopause or at the end of menstruation, it should be taken seriously, and the patient should go to the hospital as soon as possible to complete the examination, so as to make a clear diagnosis and carry out targeted treatment in a timely manner.