Postnatal Growth at 64 Weeks Postmenstrual Age in Preterm Infants Delivered at ≤ 34 Weeks' Gestation: A Single Center Study.

OBJECTIVE: To study the postnatal growth at 64 weeks postmenstrual age (PMA) in preterm neonates born at ≤ 34 weeks gestational age. METHODS: A cross-sectional study was conducted between August, 2019 and November, 2021, wherein, we took anthropometric measurements of neonates (delivered at ≤ 34 weeks' gestation) at 64 (± 2) weeks PMA. The rapidity of postnatal growth was categorized according to change in the z-score of anthropometric measures, viz, weight-for-age, length-for-age and head circumference-for-age, between birth and 64 weeks PMA. For each of the growth parameters, growth rate was categorized according to the change in z-score (z-score at 64 weeks PMA minus z-score at birth) as slow (< -0.67), acceptable (-0.67 to < 0.67), and rapid (≥ 0.67). RESULTS: Out of the 156 preterm neonates evaluated, weight gain was slow, acceptable and rapid in 95 (60.8%), 45 (28.9%), and 16 (10.3%), respectively. Length gain was slow, acceptable, and rapid in 87 (55.7%), 49 (31.4%), and 20 (12.9%) infants, respectively. Head circumference gain was slow, acceptable and rapid in 103 (66.5%), 42 (26.5%), and 11 (7.0%) infants, respectively. The risk [aOR (95% CI)] for slow weight gain increased with early initiation of complementary feeding [8.0 (3.5, 18.0)] and decreased with a longer duration of EBF [0.4 (0.2, 0.6), P < 0.001]. The risk for rapid weight gain also decreased with the longer duration of EBF [0.27 (0.1, 0.5), P < 0.001]. Gestational age < 32 weeks ,weight for gestation at birth, and re-hospitalization following discharge were the other key factors influencing the growth rate. CONCLUSION: Among babies born preterm (≤ 34 weeks), more than half had slow gain in weight, length and head circumference. EBF till 6 months corrected age was protective against slow and rapid weight gain.

Anthropometric measurements and body composition of preterm infants born ≤34 weeks at 12-13 months corrected age as compared to term infants.

BACKGROUND: Growth in the first year of life depends primarily on nutrition. Currently, the infant feeding practices of term babies are being extrapolated for preterms. While extrapolating, it is not clear if corrected age (CA) or chronological age should be used. In preterm infants, born ≤34 week gestation age, this difference may be more than 6 weeks. We studied the growth parameters and body composition of preterm infants born ≤34 week gestation age as compared to that of term infants at 12-13 months CA. METHODS: The growth of 99 term infants and 170 preterm infants born ≤34 weeks was evaluated at 12-13 months CA. The anthropometric measurements, body mass index (BMI) and skin fold thickness (SFT) at four sites (biceps, triceps, subscapular and suprailiac) were compared in the two groups. The sum of the SFT was taken as a marker of fat mass. RESULT: At 12-13 months CA, preterm infants had significantly less weight, length and BMI as compared to term babies. The weight and BMI for age Z-scores, weight for length Z-scores and fat mass were also significantly less in preterm babies. CONCLUSION: The anthropometry measures in preterms (<34 weeks) at 12-13 months CA were significantly lower than that of term infants. In our study population, preterms did not catch up in growth in the first year even when the CA is used for comparison. The causes could be multifactorial and need to be studied further.