Inadequate identification of small-for-gestational-age fetuses at an urban teaching hospital

To ascertain the likelihood of identifying small for gestational age (SGA) neonates prenatally (below the 10th percentile for gestational age).

On admission for delivery, the charts of singletons with reliable gestational age (GA) were reviewed to determine whether intrauterine growth restriction (IUGR) was suspected, clinically or sonographically. Multiple logistic regression analysis was used with the accurate identification of SGA as the dependent variable and 13 independent variables.

Over 10 months, 1502 pregnant women met the inclusion criteria and 16% of neonates were born SGA. Before delivery, only 10% (95% confidence interval 6%-14%) of newborns identified as SGA were detected, and 7% weighed below the 5th percentile. Multiple logistic regression analysis identified 4 factors that made a significant independent contribution to the detection of SGA: younger maternal age, size less than date, sonographic examination within 4 weeks of delivery, and a history of substance abuse.

Because we failed to identify 90% of SGA with fundal height measurements, the likelihood of detecting most growth-restricted fetuses clinically is low. If other investigators confirm these findings, a paradigm shift is warranted to improve the detection of IUGR.