Bone up on calcium.
It builds your baby's bones and teeth. If there's not enough in your diet, the fetus will draw calcium from your bones, putting you at risk for osteoporosis later in life. You need a minimum of 1,000 mg a day.
Low-fat or nonfat milk, processed cheeses, and yogurt are great sources (about 300 mg per serving), but there are many calcium-rich nondairy alternatives: calcium-fortified orange juice or tofu; sardines and canned salmon (with the bones); and dark-green, leafy vegetables. If your doctor recommends taking a calcium supplement, steer clear of those made from bonemeal or oyster shells, since they can contain dangerous levels of lead or other pollutants, and those with added vitamin D, an excess of which can harm the fetus. If you take both calcium and iron supplements, do so at different times of day, because they can interfere with each other's absorption.