Corpus callosum growth in normal and growth-restricted fetuses.

OBJECTIVE

The aim of this study was to characterize the normal ultrasonographic growth of the corpus callosum (CC) in normal and in growth-restricted fetuses throughout gestation.

METHODS

This was a prospective cross-sectional study. Consecutive routine biometric measurements and fetal organ scans were obtained in patients undergoing elective fetal anatomical surveys or evaluation of the fetal growth between 16 to 33 weeks. Special attention was given to the CC of the fetal brain. In addition, we evaluated the growth of the CC in growth-restricted fetuses throughout pregnancy.

RESULTS

Two hundred and fifty two normal fetuses were scanned between 16 and 36  weeks of gestation. A regression line of the CC was established through gestation and a second-degree correlation was found between gestational age and CC outer margin. Twenty four growth-restricted fetuses were also evaluated in which the growth of the CC was significantly below both the 25(th) and 50(th) percentiles in 77.3% and 95.5%, respectively, for the same gestational age.

CONCLUSIONS

We provide nomograms for the ultrasonographic dimensions of the fetal CC that allows for prenatal diagnosis of abnormal dimensions of CC. The significance of abnormal CC growth in growth-restricted fetuses should be further evaluated.