Longitudinal Trends in Weight, Height, and Head Circumference Z-Scores in Preterm Infants from Birth to 12 Months Post-Discharge

Background: Recently improved care of preterm neonates caused a significant increase in the survival rate of these high-risk neonates. Unfortunately, morbidities and multiple problems such as growth disorders of premature infants during and after hospitalization continue. Monitoring the growth of these infants is very important in establishing a clinical vision for performing therapeutic interventions. This study aimed to determine the height, weight, and head circumference Z-SCOREs of preterm infants. Methods: In this longitudinal study, premature infants referred to the neonatal clinic of Mahdieh and Mofid hospitals affiliated to Shahid Beheshti University of medical sciences (Tehran-Iran) from 2018 to 2023 were evaluated. Information about the height, weight and head circumference of the infants at birth and each visit was extracted from the available files. CDC growth calculator software was used to determine neonatal growth Z-scores. Results: Among 330 neonates, 157 (47.6 %) neonates were female and 173 (52.4%) were male. Weight Z-scores have a decreasing trend from birth to day 127 and then increase. In both girls and boys showed that there is a significant difference in the mean of weight, height, and head circumference Z-scores between follow-ups. With an increase of one week in the gestational age, the duration of hospitalization of newborns decreases by 68%. Conclusion : Based on the growth Z-score presented in this study, it is possible to accurately monitor the growth of premature infants.