29 Weeks Pregnant: Your Baby’s Development Temperature control. At 29 weeks pregnant, your baby's brain has matured to the point where it can help regulate body temperature. By the time she's born, she'll have hundreds of billions of nerve cells. That seems like a lot, but she won't produce any more after birth. Putting on padding. Your baby is looking more like a full-term baby these days. She's plumping up nicely; the surface of her skin is smoother and paler because of the fat she's starting to gain. This fat will be an important factor in her ability to keep warm. Your baby also has eyelashes; she may be batting them at you right now! 29 Weeks Pregnant: Your Symptoms Weight matters. At 29 weeks pregnant, your baby will be putting on most of his weight over the next three months, and so will you. You can probably expect to add about 11 pounds in the last trimester. Third-trimester complaint. Leg cramps are a common complaint during pregnancy, and experts aren't sure exactly what causes them. Some say it's the added weight on your legs, while others think the pain may signal a calcium or potassium deficiency. These cramps may also be the result of the pressure of your uterus on the nerves running to the legs. Coping with leg cramps. If you do get a cramp, gently stretch your leg, flexing your foot and pulling your toes back toward you. Stretching throughout the day and just before you go to bed may help too. Make sure you increase intake of calcium-rich foods during pregnancy (dairy products are a good choice), as well as those that contain a lot of potassium.