Second-trimester measurements of placental volume by three-dimensional ultrasound to predict small-for-gestational-age infants.

OBJECTIVE

The objective of this study was to investigate the value of second-trimester three-dimensional sonographic placental volume measurements to predict infants who are below the 10th centile for birth weight.

SUBJECTS AND METHODS

Placental volume measurements were performed using three-dimensional ultrasound in 382 women with normal singleton pregnancies at 16-23 weeks' gestation. Logistic multivariate regression consisting of variables considered to influence birth weight was used to predict infants with a birth weight below the 10th centile from the placental volume measurements.

RESULTS

Prognostic influence could be shown for placental volume (p < or = 0.0001), gestational week at the time of measurement (p = 0.0002) and maternal weight at the time of registration (p = 0.0025). Values for specificity and sensitivity achieved by choosing an 'optimal' cut-off point of 0.16 for the estimation probability for a small-for-gestational-age (SGA) infant were low at 82.5% and 52.5%, respectively.

CONCLUSIONS

Three-dimensional sonographic measurement of the placental volume alone is not a satisfactory technique for predicting SGA infants.