When not in use, a healthy uterus is a small organ, measuring about 3 inches (7.5 centimeters) long and 2 inches (5 cm) wide. During pregnancy, that changes — fast. By about 20 weeks into pregnancy, the expanding uterus reaches all the way to the navel. The outer edge of the uterus reaches the lower edge of the rib cage by about 36 weeks. |