My daughter was born at 27 weeks and 4 days. After graduating from the University of Michigan Neonatal Intensive Care Unit (NICU), we quickly learned how confusing it can be to have a premature baby. They explained that our daughter is two ages, her actual age and her corrected age.
Her actual age starts from when she was born. So, six months after she was born, my little munchkin was six months “actual.” Her corrected age is from her due date, when she should have been born. So, since my daughter was born three months early, when her actual age was six months old, her corrected age was only three months old.
The most confusing part about this is that some things follow her actual age and some follow her corrected age, and some fall somewhere in the middle.
Actual age
When it comes to general doctor appointments, she follows her actual age. That means she gets vaccinations based on when she was born. This was tough for us at first in the NICU because my daughter had a strong reaction to her first round of vaccinations. She was a few months old, but gestationally, she still wasn’t even ready to have been born. She needed additional breathing support because of this, but we worked through it, and she was just fine.
Since then, we’ve followed the same vaccination schedule and it hasn’t been a problem. She’s all caught up, and even has had her Covid-19 and FLU vaccinations.
Her check-ups also follow her actual age. We see our pediatrician every month or two despite her prematurity.
RELATED: After the NICU: What Life is Like in the Months After NICU Graduation
Corrected age
We follow her corrected age for milestones. This can be a bit confusing because every app and milestone trackers out there follow term babies. If we follow my example from before where she was six months actual and three months corrected, she would not be rolling over or taking solids. Instead, she was expected to be doing tummy time, starting to vocalize more, visually track, and turn her head when we speak to her.
It’s led to some confusion, especially with family and friends. She eats solids later, crawls later, and even her clothing size is different. At six months corrected, she was just starting to fit into three months’ clothing.
Because she was a preemie, eating is her biggest struggle, so starting solids early is out of the question. Some babies start as early as four months, but my girl will be nine months actual, six months corrected before she even tastes anything. We’ll start slow with purees and build up from there.
Middle
Growth is the one thing that comes in the middle. Technically, my daughter’s growth charts line up with her actual age. However, her line falls far beneath her age, since she’s much smaller and gestationally younger. The confusing part is that they want her to catch up to her actual age despite her prematurity. Therefore, her head circumference, weight, and length all lie somewhere in the middle.
This is a little muddled to explain. I still don’t know how to respond when people ask how old my daughter is! The main takeaway is that she has two ages, but will catch up by the time she’s two years old.

