Sizing Things Up
As I learned with Jason, a newborn's measurements don't necessarily predict her future height and weight. Many factors can influence size at first, including a mom-to-be's diet and health conditions such as gestational diabetes, says W. Gregory Feero, M.D., Ph.D, a family physician and special advisor to the National Human Genome Research Institute of the National Institutes of Health. More than 100 genes code for height, and regardless of her initial numbers, your sweet pea will probably grow to her genetically predisposed stature. (But kids who have poor nutrition and little physical activity tend to be shorter despite their genetic potential, Dr. Starr says.)
How to predict your child's future height? To make a rough estimate for a girl, subtract 5 inches from Dad's height, then average that number with yours. For a boy, add 5 inches to your height, then average that figure with Dad's. Or follow your kid's growth curve: "If she's consistently in the 50th percentile for height and weight, it's likely she'll be close to that as an adult," Begleiter says. Still, you can't be sure, so even if your kid has been in the 99th percentile for months, don't bank on her scoring a volleyball scholarship just yet.