Postnatal Transitional Weight Loss and Adverse Outcomes in Extremely Premature Neonates.

Area of Science:

• Neonatology
• Perinatal Medicine
• Infant Health

Background:

• Early postnatal weight loss (EPWL) in extremely low birth weight (ELBW) infants (<1000 g) exhibits significant variability.
• Previous studies suggest EPWL is unassociated with adverse outcomes within a 3-21% range, potentially due to this wide variation.

Purpose of the Study:

• To investigate the impact of graded maximum EPWL (low, moderate, high) on clinical outcomes in ELBW infants.
• To determine if EPWL is an independent predictor of adverse outcomes in ELBW infants.

Main Methods:

• Retrospective cohort observational study of ELBW infants.
• Maximum weight loss (MWL) from birth weight was calculated and categorized into low (5-12%), moderate (12-18%), and high (18-25%) groups.
• Clinical course and complications were compared across MWL groups, with adjustments for gestational age (GA).

Main Results:

• Infants in the low MWL group had higher GA and required less surfactant and respiratory support.
• While initial comparisons showed differences in oxygen dependency and fluid balance, these became non-significant after controlling for GA.
• Maternal pregnancy-associated hypertension was more prevalent in mothers of infants with low MWL (38%) compared to the high MWL group (0%).

Conclusions:

• Maximum postnatal weight loss in ELBW infants is not independently associated with adverse clinical outcomes when gestational age is considered.
• Maternal hypertension appears to be a factor that decreases EPWL in ELBW infants.