How does an infant's height change during the first year?

During the first year of life, an infant's height typically doubles from their birth length. This significant growth occurs due to rapid physical development, as infants undergo consistent changes in size and shape during their early months. The average newborn is about 20 inches long at birth, so by the time they reach their first birthday, they will likely be around 30 inches tall, effectively doubling their height.

The growth pattern is influenced by a variety of factors, including nutrition, genetics, and overall health. While infants may experience growth spurts, particularly during the first few months, the general rule is that their height will double by the end of the first year. This vital growth helps lay the foundation for their future physical development as they transition into toddlerhood.