29 Weeks

Your baby now weighs about 2 1/2 pounds (like a butternut squash) and is a tad over 15 inches long from head to heel. His muscles and lungs are continuing to mature, and his head is growing bigger to make room for his developing brain. To meet his increasing nutritional demands, you'll need plenty of protein, vitamins C, folic acid, and iron. And because his bones are soaking up lots of calcium, be sure to drink your milk (or find another good source of calcium, such as cheese, yogurt, or enriched orange juice).

Your baby's very active now and some old friends — heartburn and constipation — may take center stage now. Some women get something called "supine hypotensive syndrome" during pregnancy. This happens when lying flat on your back causes a change in heart rate and blood pressure that makes you feel dizzy until you change position. You might notice that you feel lightheaded if you stand up too quickly, too. To avoid "the spins," lie on your side rather than your back, and move slowly as you go from lying down to sitting and then standing.