Assessment of fetal growth using the ratio of the transverse cerebellar diameter to abdominal circumference

Abstract

ObjectiveTo evaluate use of the transverse cerebellar diameter to abdominal circumference (TCD/AC) ratio in predicting intrauterine growth restriction (IUGR). MethodsA prospective observational study was conducted at a prenatal clinic in Udaipur, India, between August 2011 and December 2012. Women with a singleton pregnancy and a confirmed gestational age of 20–36 weeks were enrolled. Transverse cerebellar diameter and abdominal circumference were measured by ultrasonography on two prenatal visits at early (20–28 weeks) and late (30–36 weeks) gestation. A TCD/AC ratio above the 90th percentile was considered to indicate IUGR. Birth weight was recorded. ResultsOverall, 100 women completed the study. Among 15 neonates with IUGR, the mean TCD/AC ratio was 14.17 ± 0.89 at early gestation and 15.61 ± 1.18 at late gestation. The TCD/AC ratio for appropriate-for-gestational-age neonates was significantly lower: 13.50 ± 0.97 and 13.80 ± 0.97 at early and late gestation, respectively (P<0.05 for both). Among 14 fetuses with a TCD/AC ratio above the 90th percentile at early gestation, 9 (64%) were small for gestational age, 5 (36%) were appropriate for gestational age, and none was large for gestational age at the neonatal examination. ConclusionThe TCD/AC ratio was fairly accurate in recognizing abnormal fetal growth at an early gestational age.