Small for gestational age
Small for gestational age (SGA) newborns are those who are smaller in size than normal for the gestational age, most commonly defined as a weight below the 10th percentile for the gestational age.
Being small for gestational age is either:
Being constitutionally small, wherein the state is basically a genetic trait of the baby.
The Intrauterine growth restriction condition is determined by birth weight and/or length.
Intrauterine growth restriction, is generally diagnosed by measuring the mother’s uterus, with the fundal height being less than it should be for that stage of the pregnancy.
The risk of SGA culminates in a final common pathway of reduced uterine-placental perfusion and decreased transfer of fetal oxygen and nutrition.
Ninety percent of babies born SGA catch up in growth by the age of 2.
All SGA babies are watched for signs of failure to thrive, hypoglycemia and other conditions.
Hypoglycemia is common in
asymmetrical SGA babies.
Asymmetrical SGA babies have larger brains that burn calories at a faster rate than their usually limited fat stores hold.
Not all newborns that are SGA are pathologically growth restricted and, in fact, may be constitutionally small.
THE SGA designation has prognostic importance because it predicts susceptibility to hypoglycemia, hypothermia, and polycythemia.
SGA associated with intrauterine growth restriction a condition in which a fetus is unable to achieve its genetically determined potential size.
Infants born SGA with severe short stature are defined as having a length less than 2.5 standard deviation scores below the mean.
A low birth weight baby is defined as an infant with a birth weight of less than 2500 g (5 lb 8 oz), regardless of gestational age at the time of birth.
A very low birth weight newborn is less than 1500 g, and an extremely low birth weight infant is less than 1000 g.
Normal Weight at term delivery is 2500 g – 4200 g.
SGA is not a synonym of low birth weight, very low birth weight, or extremely low birth weight.
The incidence of low birth weight in developed countries is 8.1%, and it is 6–30% in developing countries.
Much of this can be attributed to the health of the mother during pregnancy.
One third of babies born with a low birth weight are also small for gestational age.
Infants that are born at low birth weights are at risk of developing neonatal infection.
There is currently no effective prevention or therapy for SGA.
A randomized controlled trial of pregnant women at high risk for SGA found that a structured Mediterranean diet or mindfulness-based stress reduction, compared with usual care, significantly reduce the percentage of newborns with SGA (Crovetto F).