29 Weeks

Your baby is growing rapidly now. This week he 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 getting bigger to accommodate his growing brain – which is busy developing billions of neurons. Every day, about 200 milligrams of calcium is deposited in your baby's skeleton, which is now hardening. With this rapid growth, it's no surprise that your baby's nutritional needs reach their peak during this trimester.