Pregnant Woman with Fetus at 5 Months lateral view
A woman's body undergoes enormous changes during pregnancy. The heart must work harder, as cardiac output increases 30-50% during pregnancy. Joints and ligaments become more elastic so that the pelvis can stretch during child birth. As the uterus enlarges, it reaches the level of the navel by 20 weeks and the lower edge of the rib cage by 36 weeks. Breasts enlarge and the number of milk glands increases in preparation for producing milk. The kidneys must work harder due to the increasing volume of blood they filter, which reaches its maximum at 16-24 weeks and remains at that level until delivery. Image 2 of 3.