birthweight vs birth weight

Some examples from the web:

• Jan 22, 2015 ... Number of babies born low birthweight (less than 2500 grams): 315,099; Percent born low birthweight: 8.0%; Percent born very low birthweight: ...
• Low birthweight is when a baby is born weighing less than 5 pounds, 8 ounces. About 1 in every 12 babies in the United States is born with low birthweight.
• The incidence of low birthweight, defined as the proportion of newborns weighing less than 2,500 grams, is monitored through both health system surveillance ...
• Abstract. Birthweight is one of the most accessible and most misunderstood variables in epidemiology. A baby's weight at birth is strongly associated with ...

Some examples from the web:

• There have been numerous studies that have attempted, with varying degrees of success, to show links between birth weight and later-life conditions, including ...
• Jun 4, 2015 ... Birth weight is the first weight of your baby, taken just after he or she is born. A low birth weight is less than 5.5 pounds. A high birth weight is ...
• What does low birth weight mean? You'll hear this term if your baby weighs less than 2.5kg (5.5lb) when she's born. About six in 100 babies who are born in the ...
• Very Low and Extremely Low Birthweight Infants. INTRODUCTION and DEFINITIONS: Low birth weight infants are those born weighing less than 2500 g.