Adjusted Age Calculator

What is corrected age?

This is the age adjusted for the period of prematurity. When assessing the development of a premature baby in the first 12-18 months after birth, doctors and parents subtract from the baby’s calendar age the weeks by which he was born earlier.

For example: the calendar age of the child is 4 months (i.e. 16 weeks). The child was born at 28 weeks of gestation, i.e. 12 weeks earlier (full-term birth at 40 weeks). The corrected age of the child is 16-12=4 weeks (1 month).This means that if a child should normally start crawling at about 9 months, a child born 3 months earlier can start crawling before 12 months, and this is not considered a pathology. Also, if the child was seriously ill and, for example, was on artificial ventilation, this will affect development. In this case, some delay does not indicate brain damage, but a lack of external stimulation during this period. The child will learn everything a little later.

Age correction is used in premature infants with very low and extremely low birth weight until the end of the 2nd year of life.

Why does my baby’s adjusted age differ from the actual age?

Your baby’s adjusted age differs from their actual (chronological) age because the adjusted age accounts for the time your baby may have missed in the womb if they were born prematurely. This helps to more accurately reflect their developmental stage compared to full-term babies. Here’s a breakdown:

Chronological Age

• This is your baby’s age based on their birth date. It is calculated as the time that has passed since their birth.

Adjusted Age

• Adjusted age (also known as corrected age) considers the number of weeks your baby was born early. It is calculated by subtracting the number of weeks of prematurity from their chronological age.

For example:

• If a baby was born 8 weeks early (32 weeks gestation instead of 40 weeks) and is now 16 weeks old chronologically, their adjusted age would be: $$\text{Adjusted Age}=\text{Chronological Age}-\text{Weeks Born Early}$$ $$\text{Adjusted Age}=16\text{ weeks}-8\text{ weeks}=8\text{ weeks}$$

Why the Difference?

• Babies born prematurely might take longer to reach certain developmental milestones than full-term babies. Adjusted age helps healthcare providers and caregivers evaluate a premature baby’s growth and progress relative to when they would have been born at full term.

When is Adjusted Age Used?

• Typically, adjusted age is used until about 2 years of age. By this time, most premature babies catch up developmentally to their full-term peers.

Using adjusted age ensures fair comparisons when tracking milestones like sitting up, crawling, or walking, helping parents and doctors focus on progress relative to the baby’s developmental starting point.

Why do we need the adjusted age calculator for prematurity?

The adjusted age calculator for prematurity is essential for evaluating the developmental progress of premature babies. Here’s why it is needed:

1. Accurate Developmental Tracking

Premature babies are born before completing the full 40 weeks of gestation. Since their physical and neurological development was interrupted, they often achieve developmental milestones later than full-term babies of the same chronological age. Adjusted age accounts for the time they missed in the womb, providing a more accurate measure of their developmental progress.

2. Fair Comparison with Full-Term Babies

Using chronological age (actual age since birth) can place premature babies at an unfair disadvantage when comparing their milestones with full-term peers. Adjusted age allows parents and healthcare providers to assess milestones based on when the baby would have been born full-term, ensuring fair and meaningful comparisons.

3. Milestone Evaluation

Pediatricians use adjusted age to determine if a baby is on track for milestones like:

• Rolling over
• Sitting up
• Crawling
• Walking
• Speech and language development

Without adjusting for prematurity, premature babies might appear delayed when, in fact, they are developing appropriately for their adjusted age.

4. Guiding Early Intervention

If a premature baby is not meeting milestones for their adjusted age, it can signal the need for early intervention therapies (like physical or speech therapy). Using adjusted age helps identify potential delays that might otherwise be overlooked.

5. Reassurance for Parents

For parents of premature babies, adjusted age provides a realistic expectation of when their child might reach milestones, reducing unnecessary worry about “delayed” development when compared to full-term peers.

6. Temporary Adjustment

The use of adjusted age is typically limited to the first two years of life. After that, most premature babies catch up to their peers, and chronological age becomes the standard measure.

In summary, the adjusted age calculator is a critical tool for understanding and supporting the unique developmental journey of premature babies, helping to provide tailored care and reducing undue stress for parents.