First-trimester ultrasound volumetry: measurement techniques and potential application in the prediction of pregnancy complications

First-trimester prediction of intrauterine growth restriction (IUGR), preeclampsia (PE), birthweight, aneuploidy, miscarriage, complications in multiple pregnancies and homozygous α0-thalassemia is a challenging and emerging field. Placenta volumes (PV) and embryo volume/fetal volume ratios are correlated with crown–rump length (CRL) or gestational age. Measurement of PV or placental quotient (PV/CRL ratio) is an early method to identify impaired trophoblast invasion and predict subsequent development of IUGR or PE. In early-onset IUGR caused by triploidy, or trisomy 13 or 18, a larger deficit in fetal volume than CRL is observed. Fetal and placental volume measurements may be applied to predict other conditions such as aneuploidy, miscarriage or stillbirth. Standardization of the 3D volumetric methodology is needed to improve reproducibility of measurement. Further studies are required to determine the use of first-trimester volumetry alone or in combination with Doppler ultrasound and other parameters t...