Evaluation of intrauterine growth pattern of twins by linear discriminant analysis of the values of biparietal diameter, femur length and abdominal circumference

In a cross-sectional study, the intrauterine growth pattern of 32 twins was compared to that of 205 singletons by analysis of the coefficients of the equations of biparietal diameter (BPD), femur length (FL) and abdominal cir cumference (AC). Lower values were observed in twins from the 20th week. BP D and AC curves showed a progressively diverging pattern, and yielded diffe rent coefficients of equations. AC showed the highest discriminant capacity followed by BPD and FL. Combined values of the two series solved by discri minant function output produced an overlapping of 58%. Based on our data, n omograms of growth of singletons should not be used for twins.