Relationship between parameters of early growth in Israeli infants

Estimating birth weight from observed postnatal weights in a Guatemalan highland community

OBJECTIVE

Low birth weight is one of the leading contributors to global perinatal deaths. Detecting this problem close to birth enables the initiation of early intervention, thus reducing the long-term impact on the fetus. However, in low-and middle-income countries, sometimes newborns are weighted days or months after birth, thus challenging the identification of low birth weight. This study aims to estimate birth weight from observed postnatal weights recorded in a Guatemalan highland community.

APPROACH

With 918 newborns recorded in postpartum visits at a Guatemalan highland community, we fitted traditional infant weight models (Count's and Reeds models). The model that fitted the observed data best was selected based on typical newborn weight patterns reported in the medical literature and previous longitudinal studies. Then, estimated birth weights were determined using the weight gain percentage derived from the fitted weight curve.

MAIN RESULTS

The best model for both genders was the Reeds2 model, with a mean square error of 0.30 kg2 and 0.23 kg2 for male and female newborns, respectively. The fitted weight curves exhibited similar behavior to those reported in the literature, with a maximum weight loss around three to five days after birth, and birth weight recovery, on average, by day ten. Moreover, the estimated birth weight was consistent with the 2015 Guatemalan National Survey, no having a statistically significant difference between the estimated birth weight and the reported survey birth weights (two-sided Wilcoxon rank-sum test; [Formula: see text]).

SIGNIFICANCE

By estimating birth weight at an opportune time, several days after birth, it may be possible to identify low birth weight more accurately, thus providing timely treatment when is required.

Decreased head circumference velocity as related to developmental deficit in infancy

We evaluated the significance of head circumference growth velocity as related to developmental deficits during infancy. Head circumferences, lengths, and developmental diagnoses were retrieved in a standard manner at ≥ 2 time points from 437 infants with developmental deficits, and 3909 normally developing infants. Infants' ages ranged from 1-24 months, with final diagnoses ascertained at age 24 months. Increased velocity during the first 2 months in typical infants was evident in the study group during the period 2-4 months. A differential head circumference growth velocity was observed, and infants diagnosed with motor delay presented decreased velocity between ages 2-4 months, compared with infants receiving other nonmotor developmental diagnoses. These differences remained after controlling for birth weight and length. No significant sex effect was evident. Infants with developmental deficits demonstrate delayed acceleration of head circumference velocity, compared with typical infants in the first 2 months. Infants with motor delay manifest decreased velocity, compared with infants presenting other developmental deficits. These differences may be related to delayed white matter maturation.