The baby’s skin is thickening and developing layers this week, under the protection of the vernix. Skin layers include the epidermis, the outermost layer of skin; the dermis, the middle layer, which makes up 90 percent of the skin; and the subcutis, the deepest layer of skin, made up mostly of fat. Your baby’s hair and nails continue to grow. If you could sneak a peek at your baby this week, you would see a fetus remarkably baby-like in appearance, with thin eyebrows, hair on the scalp and rather well-developed limbs.
Now, 20 weeks pregnant, you've probably begun to feel your baby’s movements. Make a note of the date, and tell your care provider at your next visit. While most of baby’s organs are structurally developed or nearing development, your baby is still quite small. But by the end of this month, he or she will finally pass the 1 pound mark!
Your uterus is enlarging quite rapidly now so that you look pregnant. Your navel may be flattened or pushed out and it will stay this way until after the birth. Heartburn may start to become a problem because the uterus is starting to push against your stomach.
Vernix, a white greasy substance, is starting to form over the baby’s skin to protect it from the amniotic fluid. This usually wears off before the birth, but sometimes traces at it can be seen. At this stage in your pregnancy the baby weighs around 10.6 ounces (300 grams) and measures about 6.5 inches (16,5 cm).