DIAGNOSTIC VALUE OF MACROSOMIA’S PREDICTOR

Abstract

Determination of the expected weight of the fetus and the diagnosis of complications in childbirth
remains debated issue. To select the optimum tactics of labor with large fetus and reduce the
complications accurate methods of prenatal prediction of macrosomia are required.
Research objectives: to evaluate the diagnostic value of ultrasound measurement of abdominal
circumference, as a predictor of macrosomia.
Materials and Methods: Study design: US -skrining. The study group included 147 birth stories with
large fetus. Selection of cases in the control group held "random digits generator Randomus-" in the
program. The control group included 328 physiological childbirth. Statistical processing performed using
SPSS software, version 20.
Results: The regression analysis was conducted to evaluate the linear relationship between
abdominal circumference (OC), biparietal diameter (BPD), the length of the thigh bone (LTB), and birth
weight (BW). The relative prognostic importance of the independent variable - AC ≥350 mm., has a
statistical significance at p = 0,001. For variables LTB and BPD, which are the main indicators to
measure the supposed fetal weight, p-value at the level of 0.793 and 0.803 respectively, indicating a low
significance of these measurement in the prediction of fetal weight.
Sensitivity = a / a + c = 125/147 = 85%, the test result indicates that, when the AC ≥ 350 mm, 85%
of the child will be born with a body weight of more than 4000 grams. Specificity = d / a + d = 312/328 =
95%, 95% excludes women without large fetus. Evaluation of diagnostic accuracy of the expected
weight of the fetus with a measuring of AC more than 350mm, is a highly sensitive and highly specific
method. The positive predictive value was 88.6%, and a negative result - 93.4%.
Conclusions: The diagnosis of a large fetus by ultrasound measurement of the circumference of the
abdomen is the most informative (p = 0.001). Given the sensitivity of 85% and specificity of 95%, AC
≥350 mm may be used as a predictor of macrosomia.