Patent ID: 7315787

Claim:
A method of assessing a patient's risk of having a fetus with a fetal abnormality comprising: determining the patient's a priori risk of having a fetus with the fetal abnormality; determining a bi-parietal diameter to occipito-frontal diameter (BPD/OFD) ratio of a patient's fetus during the first trimester of pregnancy; determining an at least one secondary marker measurement corresponding to the patient during a first trimester of pregnancy; performing a comparison of the BPD/OFD ratio of the patient's fetus and the at least one secondary marker measurement corresponding to the patient with observed relative frequency distributions of fetal BPD/OFD ratios and at least one secondary marker measurements from observed affected and observed unaffected pregnancies; and assessing the patient's risk of having a fetus with a fetal abnormality in view of a result of the comparison and the patient's a priori risk of having a fetus with the fetal abnormality, wherein the fetal abnormality is a craniofacial abnormality, a chromosomal abnormality, or a developmental central nervous system abnormality.