- Biparietal diameter (BPD)
- Crown-Rump Length (CRL)
- Femur length - (FL) is used to determine fetal age and normal development (small/large/abnormal) parameters. The femur is the longest bone in the body and measurements and reflects the longitudinal growth of the fetus (approximately 14 weeks 1.5 cm - term 7.8 cm). It is one of the four typical ultrasound assessments of fetal size and age: Biparietal Diameter (BPD), Head Circumference (HC), Abdominal Circumference (AC), and Femur Length (FL).
- Functional linear discriminant analysis (FLDA) - new growth assessment technique using serial measurements to discriminate between normal and abnormal fetal growth.
- Head Circumference (HC)
- Gestational sac (GS) size
- inversion mode - an ultrasound processing method of volume analysis for the visualization of fluid-filled fetal structures such as; heart chambers, vessel lumen, stomach, gallbladder, renal pelvis, and the bladder. Post-processing inverts the gray scale of the volume voxels showing the normally anechoic structures in 3D or 4D renderings. This technique has been used to identify cardiac anomalies.
- Linear discriminant analysis (LDA) to longitudinal data (James and Hastie, 2001)
- Mean gestation sac diameter (MSD)
- Mean yolk sac diameter (MYD)
- Spatiotemporal image correlation (STIC) - an image acquisition method used mainly for fetal heart analysis. Requires two steps; an automatic volume sweep, then image data analysis according to spatial and temporal domain generating an online dynamic 3D image sequence.
- Transvaginal scan (TVS)
- Termination of pregnancy (TOP)