very low birth weight
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1. heaviness; the degree to which a body is drawn toward the earth by gravity. (See also Tables of Weights and Measures in the Appendix.) Abbreviated wt.
2. in statistics, the process of assigning greater importance to some observations than to others, or a mathematical factor used to apply such a process.
apothecaries' weight see apothecaries' system.
atomic weight the sum of the masses of the constituents of an atom, expressed in atomic mass units (or daltons), in SI units (i.e., kilograms), or as a dimensionless ratio derived by comparing the mass to the mass of an atom of carbon-12, which is taken as 12.000. Abbreviated At wt.
avoirdupois weight see avoirdupois system.
equivalent weight the amount of substance that combines with or displaces 8.0 g of oxygen (or 1.008 g of hydrogen), usually expressed in grams; for acid/base reactions, one equivalent donates or receives a mole of protons and the equivalent weight is the ratio of the molecular weight to the number of protons involved in the reaction. For oxidation-reduction reactions, one equivalent donates or receives a mole of electrons and the equivalent weight is the ratio of the molecular weight to the number of electrons involved in the reaction.
gram molecular weight the molecular weight of a substance expressed in grams; one gram molecular weight of a molecular substance contains one mole of molecules. See also mole1.
low birth weight (LBW) see under infant.
molecular weight the weight of a molecule of a chemical compound as compared with the weight of an atom of carbon-12; it is equal to the sum of the weights of its constituent atoms and is dimensionless. Abbreviated Mol wt or MW. Although widely used, the term is not technically correct; relative molecular mass is preferable.
very low birth weight (VLBW) see under infant.
very low birth weightVLBW Neonatology Referring to an infant weighing between 1000 g and 1500 g at birth; these children are at high risk for neurobehavioral dysfunction, poor school performance. See Low birth weight. Cf Extremely low birth weight.
Very Low Birth Weight infants–outcomes
Birthweight ≤ 750 g 750-1.5 g ≥ 1.5 Kg
Sample number 68 65 61
MPC score* 87 93 100
Mental retardation (IQ < 70) 21% 8% 2%
Poor cognitive function 22% 9% 2%
Poor academic skills 27% 9% 2%
Poor gross motor function 27% 9% 0%
Poor adaptive function 25% 14% 2%
Cerebral palsy 9% 6% 0%
Severe visual disability 25% 5% 2%
Hearing disability 24% 13% 3%
↓ Weight/height/head size 22/25/35% 11/5/14% 0/0/2%%
*Mental Processing Composite score
ver·y low birth weight(VLBW) (ver'ē lō bĭrth wāt)
Infant weighing less than 1500 g at birth. Can be due to a range of factors including interference with intrauterine growth or premature birth.