Does Your Baby Have Two Birthdays?

Was your baby born on her due date? Roughly 62% of babies are born within a week of the day they’re expected, but your doctor’s estimate may be a couple of weeks off without causing worry. If your baby was born a bit early, though, you might find it useful to think of her as having two birthdays for the first year or two of her life.


Children grow and develop at different rates, but there are common milestones of development. When you take your baby in for his regular check ups, your pediatrician will check for these milestones.

For example, a two month old baby may smile at people, and a four month old almost certainly will. A nine month old can usually sit up and a twelve month old will usually copy meaningful gestures like waving or nodding.

Seeing these predictable developments in mental or physical growth lets your pediatrician see that your baby is growing at the typical rate. If there is any reason to be concerned about your child’s development, your doctor will discuss these concerns with you.

Early babies

If your baby is a premie — born earlier than 37 weeks — then you have already had many conversations about development with your pediatrician by the time you begin to think about milestones like walking and talking.

A baby who was born at 38 or 39 weeks, however, is not premature. But she may be a little early. Some studies have found that early term babies are likely to be a little bit behind their peers at one year and even when they begin school.

When comparing your child with milestones on your favorite app or in parenting magazines, count from your due date as well as from your baby’s birthday. If your child was born a week early, he might reach that four month milestone four months from his due date, not four months from his birthday.

Should you worry?

Research on early term babies — those born at 38 or 39 weeks — often focuses on moms who choose to schedule an early C section instead of waiting. But many moms anxiously watch their children for the new behavior their favorite mommy vloggers say will be showing up this week.

If that sounds familiar, you might need to give your child a couple of weeks. He might reach that milestone closer to his due date than to his birthdate.

Remember, milestones are based on averages, and children develop at different rates. If you’re concerned, ask your pediatrician. In the meantime, enjoy your child’s uniqueness.