Premature baby growth
How to think about weight, length and head circumference in premature babies, using corrected age, follow-up and signs to report.
Growth in a premature baby should be interpreted with the team following them. Comparing weight with a term newborn is not enough: corrected age, clinical history and trend over time matter.
What is measured
At appointments, clinicians usually look at:
- weight;
- length;
- head circumference;
- feeding pattern;
- wet and dirty diapers;
- tone, energy and behavior.
One number matters less than the overall trend. Steady growth on a lower percentile can be reassuring if the team considers it appropriate.
Corrected age and charts
For many premature babies, corrected age is used when interpreting growth and development. Some services use preterm-specific charts at first and then move to other pediatric charts.
Do not change milk, fortifier or feeding schedule just because of an online chart. For premature babies, these decisions need to be individualized.
Signs to report
Contact your pediatrician or neonatal team if you notice:
- shorter or very tiring feeds;
- sleepiness that prevents feeding;
- frequent or green vomiting;
- fewer wet diapers;
- weight that is flat or falling according to the plan you were given;
- breathing difficulty during feeds;
- bluish, gray or very pale color.
If your baby is poorly responsive, struggling to breathe or unable to feed, get help right away.
Feeding
Some premature babies need fortified breast milk, special formula, vitamins or iron. Others do not. The choice depends on gestational age, weight, blood tests, growth and diagnoses.
To avoid errors:
- use the written doses;
- do not dilute or concentrate milk on your own;
- report spit-up, tiredness, sweating or coughing during feeds;
- bring the diary to appointments if requested.
Helpful questions at visits
You can ask:
- which chart is being used;
- what weight gain is expected in the next weeks;
- when to weigh at home and when to avoid too-frequent weighing;
- which signs should prompt a call;
- when fortifier, formula, vitamins or iron should be reviewed.
Useful links
Sources and further reading
- Your Preemie's Growth & Developmental Milestones - HealthyChildren.org - American Academy of Pediatrics
- Corrected Age For Preemies - HealthyChildren.org - American Academy of Pediatrics
- Child growth standards - World Health Organization
- Fever and Your Baby - HealthyChildren.org - American Academy of Pediatrics
- CDC's Developmental Milestones - Centers for Disease Control and Prevention
Sources are used to support general informational content and do not replace advice from a pediatrician or healthcare professional.
