Fetal growth restriction at term: myth or reality?

To evaluate the morbidity and mortality associated with the small for gestational age (SGA) fetus born at term to an otherwise uncomplicated pregnancy.

Small for gestational age, singleton newborns (birth weight below the tenth percentile for gestational age) born at 37-42 weeks' gestation were identified by medical record discharge coding. We excluded gestations complicated by structural or chromosomal abnormalities, maternal diabetes mellitus, preeclampsia, chronic hypertension, asthma, or renal, endocrine, or autoimmune disease. Three low-risk, appropriate for gestational age (AGA) fetuses, matched for gestational age at delivery, were selected randomly for each SGA fetus and served as controls. Maternal and neonatal data were abstracted via medical record review. Statistical analysis included chi2 Fisher exact test, and analysis of variance.

There were 67 newborns in the study group and 201 in the control group. There were no fetal or neonatal deaths in any of these cases. The maternal age at delivery, prepregnancy weight, race, smoking status, weight gain during pregnancy, and neonatal gender did not statistically differ between the two groups. Compared with AGA infants, a larger proportion of SGA newborns had low 1-minute Apgar scores and SGA newborns were more likely to be admitted to the neonatal intensive care unit, and have respiratory distress, hypoglycemia, thrombocytopenia, and hyperbilirubinemia. They were also significantly more likely to be delivered by cesarean.

The SGA newborn from an uncomplicated pregnancy delivered at term has increased neonatal morbidity compared with its AGA counterpart. These results dispute the notion that term growth restriction is a benign condition.