The endometrial thickness of 1.2 cm is determined on ultrasound. The endometrium is a functional layer that undergoes cyclic changes influenced by hormone levels. Normally, an endometrial thickness of 12 mm should be expected during the ovulation phase of menstruation when the endometrium appears to thicken. The thickness of the endometrium is influenced by ovarian hormones. at the end of the menstrual cycle, the endometrium is 4mm. as the menstrual cycle changes, the endometrium thickens and may reach 8mm at the time of ovulation. before the menstrual cycle, that is, after ovulation, the endometrium may reach 14mm. ultrasound indicates that the endometrium is 1.2cm thick, probably after ovulation. The endometrial manifestation before menstruation.