The premature infant: How old is my baby?
Babies who are born prematurely often have two ages:
- Chronological age is the age of the baby from the day of birth—the number of days, weeks or years old the baby is.
- Adjusted age is the age of the baby based on his due date. Health care providers may use this age when they evaluate the baby's growth and development. So, if a baby is 6 months old, but was born two months early, his adjusted age is 4 months.
What to say when someone asks
This is up to you.
- You can say, "He's 6 months old, but he was born two months early. That's why he looks like a 4-month-old."
- Or you can say, "He's 6 months old" and leave it at that.
Remember: When people ask about your baby, they usually are being kind, not nosy.
Calculating your baby's adjusted age
Here's how to calculate your baby's adjusted age:
- Chronological age: 20 weeks
- The number of weeks your baby was premature: 6 weeks
- Subtract the number of weeks premature from the chronological age (this is your baby's adjusted age): 20 weeks minus 6 weeks equal 14 weeks.
- Divide your baby's adjusted age in weeks by 4 to determine your baby's adjusted age in months: 14 divided by 4 equals 3 ½ months.
See also: Share your story
Last reviewed: August, 2014