Facial Floor Measurements at Second Trimester Scan and Relations to Biparietal Diameter and Head Circumference

ABSTRACT Introduction Prenatal assessment of facial morphology offers valuable insights into craniofacial malformations and aneuploidies, characterized by distinct craniofacial features. This study aimed to evaluate the correlation between twelve facial measurements across the three levels of the face and the predictive value of cranial biometric parameters such as biparietal diameter (BPD) and head circumference (HC). Methods Data were extracted from obstetrical records and included twelve facial measurements across upper, middle, and lower facial levels, as well as biometric parameters such as BPD and HC. Correlation analyses between each measurement and BPD/HC and multiple linear regression models were constructed to evaluate the predictive value of BPD and HC. Results Correlation analyses revealed weak but significant associations ( r < 0.25) between most facial variables and both BPD and HC, with BPD showing stronger and more consistent relationships. In regression models, BPD emerged as a significant predictor of facial dimensions in the upper and middle levels ( p < 0.001), while HC showed fewer significant associations. Conclusions HC appears to be a stronger predictor of these differences in facial dimensions than BPD. Further validation in larger, prospective cohorts is recommended to confirm these associations and enhance clinical applicability.