Small for gestational age (SGA)

Definition

Small for gestational age (SGA) means a fetus or infant is smaller in size than normal for the baby's gender and gestational age.

Alternative Names

Intrauterine growth restriction (IUGR); Low birth weight

Information

Ultrasound is used to find out if a fetus is smaller-than-normal for age (intrauterine growth restriction). The most widely used definition of SGA is birth weight below the 10th percentile.

A fetus with intrauterine growth restriction will be small in size and can have problems such as:

• Increased red blood cells (polycythemia)
• Low blood sugar (hypoglycemia)
• Low body temperature (hypothermia)

References

Baschat AA, Galan HL, Ross MG, Gabbe SG. Intrauterine growth restriction. In: Gabbe SG, Niebyl JR, Simpson JL, eds. Obstetrics: Normal and Problem Pregnancies. 5th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2007:chap 29.