Three-dimensional ultrasound measurement of the placental volume in early pregnancy: Method and correlation with biochemical placenta parameters

Placental size has been an interesting topic of research for many years. Th e main aim of this study was to investigate the feasibility of measuring th e placental volume at the end of the first trimester using three-dimensiona l (3D) ultrasound and to correlate these volumes to known placental functio nal indices and to factors affecting the placenta. Women with singleton pre gnancies at the end of the first trimester were included into this study. T he volume data of the placentae were con elated to the crown-rump length (C RL), placenta-associated plasma protein A (PAPP-A), free beta-human chroang iogonadotropin (f-beta -hGG) and other factors that may affect the placenta l size or function. A total of 1462 pregnancies could be evaluated. Compari son between CRL and placental volume proved a significant correlation (r=0. 43, P <0.001). Due to the observed proportional growth of CRL and placental volume, a quotient (placental volume/CRL) was calculated for each case. Th ere were no differences between placenta/CRL-quotients in relation to gravi dity, parity or smoking. Correlations could be established between the plac ental volume and PAPP-A and f-beta -hCG (PAPP-A: r =0.28, P <0.001, f-beta -hCG: r=0.10, P <0.001). The measurement of the placenta in the first trime ster can be performed in a high percentage of cases. The placenta/CRL quoti ent represents a simple method to compare placentae from different gestatio nal days. The correlation between placental volume and maternal serum scree ning parameters might provide a chance to refine first trimester Dean's syn drome serum screening. Future studies will be needed to evaluate the possib le clinical use of first trimester placental volume measurements. (C) 2001 Harcourt Publishers Ltd.