Objectives: to compare the accuracy of equations F.P. Hadlock and computer programs by V.N. Demidov
in determining gestational age and fetal weight in the third trimester of gestation.
Materials: 328 patients in terms 36–42 weeks of gestation are examined. Ultrasonography was performed
in 0–5 days prior to childbirth.
Results: it is established that the average mistake in determination of term of pregnancy when using the
equation of F.P. Hadlock made 12,5 days, the computer program of V.N. Demidov – 4,4 days (distinction
2,8 times). The mistake within 4 days, when using the equation of F.P. Hadlock has met on average in 23,1 %
of observations, the computer program of V.N. Demidov — 65,9 % (difference in 2,9 times). The mistake more
than 10 days, took place respectively in 51,7 and 8,2 % (distinction by 6,3 times). At a comparative assessment
of size of a mistake in determination of fetal mass it is established that when using the equation of F.P. Hadlock it has averaged 281,0 g, at application of the computer program of V.N. Demidov — 182,5 g (distinction
of 54 %). The small mistake in the mass of a fetus which isn't exceeding 200 g at application of the equation of
F.P. Hadlock has met in 48,1 % of cases and the computer program of V.N. Demidov — 64,0 % (distinction
of 33,1 %). The mistake exceeding 500 g has been stated in 18 % (F.P. Hadlock) and 4,3 % (V.N. Demidov)
respectively (distinction 4,2 times).
Conclusions: the computer program of V.N. Demidov has high precision in determination of term of a
gestation and mass of a fetus in the III pregnancy.
Simulation and high-precision wavelength determination of noisy 2D Fabry–Pérot interferometric rings for direct-detection Doppler lidar and laser spectroscopy
