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Professional Technical IVT

very low birth weight

Also written as: VLBW — very low birth weight

A birth weight classification for infants weighing between 1,000-1,499 grams at birth, indicating significant prematurity and increased medical risks.

Full Definition

Very low birth weight (VLBW) is an important neonatal classification referring to infants who weigh between 1,000 and 1,499 grams (approximately 2 pounds 3 ounces to 3 pounds 5 ounces) at birth. This category encompasses infants who are typically born between 28-32 weeks of gestation and represents a high-risk population requiring specialized neonatal intensive care. VLBW infants face increased risks of complications including respiratory distress syndrome, apnea of prematurity, feeding difficulties, temperature instability, and increased susceptibility to infections. While outcomes for VLBW infants are generally better than those for extremely low birth weight (<1,000g) infants, they still require careful monitoring and may experience long-term developmental challenges. This classification is part of a continuum that includes low birth weight (<2,500g) and extremely low birth weight (<1,000g), each with distinct risk profiles and management protocols.

Usage

Usage note: Specific weight range (1,000-1,499g) distinguishes from other birth weight categories; correlates with moderate to severe prematurity.

In Context

  • "The very low birth weight infant at 1,200 grams required continuous positive airway pressure and gavage feeding." — NICU daily progress note
  • "Neurodevelopmental follow-up is recommended for all very low birth weight infants through at least 2 years corrected age." — NICU discharge planning

Also known as

VLBW

Contrasted with

normal birth weight

Don't confuse with

extremely low birth weight low birth weight small for gestational age

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