At this point in pregnancy, the top of your uterus is about one-third of the distance between the bellybutton and the xiphoid cartilage at the lower end of your breastbone. Constipation is common because your uterus is pressing on your lower colon and hormones slow down your body’s excretion process. Between the growth of your uterus and general weight gain, you may be feeling fatigued. Some women also experience heartburn as your uterus presses against your stomach.

Your breasts are also changing to get ready for breastfeeding. First colostrum and then milk are produced by the grape-like clusters of tiny sacs (alveoli) deep within the breast tissue. Clusters of alveoli form lobules, which come together to form 15 to 20 lobes. Each lobe connects to a lactiferous duct for conveying milk. As the ducts extend toward the nipple and areola (darker area around the nipple), they widen into the lactiferous sinuses. These sinuses (or milk pools) release the milk through 15 to 20 tiny nipple openings in each breast when the baby nurses.

At week 28, the fetus is about 16 inches long and weighs two to three pounds. The skin is wrinkled but will become less so as more fat builds up under the skin in the next few weeks. Fine, downy hair called lanugo, and a waxy white protective substance covering the skin called vernix, are on the fetus’ body. Its eyes are open, and eyebrows and eyelashes were formed in the fourth month. The fetus sucks its thumb and its taste buds have developed. It kicks, stretches and moves frequently in your uterus—you’ll feel it moving around and others might even be able to see these movements!

Fetal organs and systems are quite well developed by the 28th week of pregnancy, but the final two months of gestation are important for further maturation of all body systems and organs.