06/06/2026
The uterus undergoes one of the most dramatic anatomical transformations in the human body during pregnancy. In the nonpregnant state, it measures about 8 cm in length, 5 cm in width, and 4 cm in thickness, and weighs roughly 60–70 g. By term, uterine weight increases to about 1,000–1,200 g, and its capacity expands from around 10 mL to approximately 5 liters to accommodate the fetus, placenta, and amniotic fluid.
At the beginning of pregnancy, the uterus remains a pelvic organ. By about 12 weeks, it becomes palpable just above the p***c symphysis. Around 20 weeks, the fundus typically reaches the level of the umbilicus, and by about 36 weeks, it reaches its highest point near the xiphoid process, showing how far it expands into the abdominal cavity.
This enlargement is not just stretching. The uterine wall remodels through hypertrophy and structural adaptation of the myometrium, allowing the organ to support fetal growth while maintaining the power needed later for labor. At the same time, blood flow to the uterus rises dramatically and reaches about 1 liter per minute at term, reflecting the enormous metabolic demand of pregnancy.
The ovaries remain relatively small compared with the expanding uterus, but early in pregnancy they are hormonally critical, especially through the corpus luteum, which supports progesterone production until placental hormone production takes over. Overall, this image highlights how the uterus changes from a small pelvic organ into a dominant abdominal structure capable of sustaining an entire developing human.
