What is a Low Birth Weight?

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At birth, most babies who have been carried full term weigh between 5 and 10 pounds. It is not always a cause for concern if a baby falls outside of this weight range, as there are many factors that contribute to the size of the baby such as the size of the mother’s uterus. However, some babies who have a significantly lower birth weight can have continuing health problems. A baby who is born weighing less than 3 pounds, 4 ounces is often at risk for complications.

Babies this small often have a harder time eating, gaining weight, and fighting off infections. In addition, the baby may have a low oxygen level at birth.

What Are the Causes?

Birth weight can be influenced by physical, medical, and environmental factors. One of the main causes of low birth weight is a premature delivery, classified as birth before 37 weeks. Intrauterine growth restriction (IUGR) can also cause a low birth weight, occurring when there are problems with the placenta. In addition to prematurity and IUGR, the following things can also impact a growing fetus:

  • Age: Women who are under 17 and over 35 have a higher risk of having a baby with a low birth weight
  • Ethnicity: African-American babies are at double the risk of being under weight than those born to Caucasian women
  • Behaviors: Mothers who use drugs, alcohol, and cigarettes during pregnancy have a greater risk of having a low birth weight baby
  • Number of babies: Multiple birth babies are at risk of a very low birth rate, often because they are born premature
  • Nutrition: Poor prenatal care

Low Birth Weight Treatment

Depending on the health of the baby at birth, some low weight babies may be cared for in the neonatal intensive care unit (NICU). The baby may need a temperature controlled bed, and a feeding tube will be necessary if he or she cannot suck.

Are There Any Long-Term Problems?

Many babies who are born with a low birth weight will catch up with average height and weight percentiles by 18 to 24 months of age. Some babies may have a hard time catching up developmentally. They can have intellectual and neurological problems such as cerebral palsy, blindness, deafness, and mental retardation, or chronic conditions such as diabetes and high blood pressure.

Prenatal care is essential in preventing low birth weight for your baby. Mothers should be sure to have regular doctor visits where the baby’s growth and the mother’s health are monitored. Mothers should also maintain a nutritious diet and gain the proper amount of weight during their pregnancy.