[Possibilities of ultrasonic estimation of gestational age in the second and third trimesters of pregnancy].

A total of 351 females with physiological pregnancies repeatedly (1928 examinations) underwent ultrasonic fetometry. The investigations revealed clear-cut correlations between the term of gestation and biometric parameters such as the mean diameter of the fetal head, abdomen, heart as well as the length of its foot, femur and humerus. The average mistake in the identification of pregnancy terms which was performed on the basis of simultaneous analysis of the parameters considered was 5.73 days in all terms of gestation.