Newborn weight nomograms in selected low and middle-income countries.

Growth impairment is common in low- and middle-income countries (LMIC) and may begin during early infancy, increasing morbidity and mortality. To ensure healthy infant growth, healthcare providers in high-income countries (HIC) track newborn weight change using tools developed and validated in HIC. To understand the utility of these tools for LMIC, we conducted a secondary analysis to compare weight trajectories in the first 5 days of life among newborns born in our LMIC cohort to an existing HIC newborn weight tool designed to track early weight change. Between April 2019 and March 2020, a convenience sample of 741 singleton healthy breastfeeding newborns who weighed ≥ 2000 g at birth were enrolled at selected health facilities in Guinea-Bissau, Nepal, Pakistan, and Uganda. Using a standardized protocol, newborn weights were obtained within 6 h of birth and at 1, 2, 3, 4, and 5 days, and nomograms depicting newborn weight change were generated. The trajectories of early newborn weight change in our cohort were largely similar to published norms derived from HIC infants, with the exceptions that initial newborn weight loss in Guinea-Bissau was more pronounced than HIC norms and newborn weight gain following weight nadir was more pronounced in Guinea-Bissau, Pakistan, and Uganda than HIC norms. These data demonstrate that HIC newborn weight change tools may have utility in LMIC settings.

Newborn weight change and predictors of underweight in the neonatal period in Guinea-Bissau, Nepal, Pakistan and Uganda.

In low- and middle-income countries (LMIC), growth impairment is common; however, the trajectory of growth over the course of the first month has not been well characterised. To describe newborn growth trajectory and predictors of growth impairment, we assessed growth frequently over the first 30 days among infants born ≥2000 g in Guinea-Bissau, Nepal, Pakistan and Uganda. In this cohort of 741 infants, the mean birth weight was 3036 ± 424 g. For 721 (98%) infants, weight loss occurred for a median of 2 days (interquartile range, 1-4) following birth until weight nadir was reached 5.9 ± 4.3% below birth weight. At 30 days of age, the mean weight was 3934 ± 592 g. The prevalence of being underweight at 30 days ranged from 5% in Uganda to 31% in Pakistan. Of those underweight at 30 days of age, 56 (59%) had not been low birth weight (LBW), and 48 (50%) had reached weight nadir subsequent to 4 days of age. Male sex (relative risk [RR] 2.73 [1.58, 3.57]), LBW (RR 6.41 [4.67, 8.81]), maternal primiparity (1.74 [1.20, 2.51]) and reaching weight nadir subsequent to 4 days of age (RR 5.03 [3.46, 7.31]) were highly predictive of being underweight at 30 days of age. In this LMIC cohort, country of birth, male sex, LBW and maternal primiparity increased the risk of impaired growth, as did the modifiable factor of delayed initiation of growth. Interventions tailored to infants with modifiable risk factors could reduce the burden of growth impairment in LMIC.