A total of 160 singleton and full-term pregnant women who delivered successfully in our department of obstetrics and gynecology from March 2017 to October 2019 were randomly selected as the study objects. Inclusion criteria: between the ages of 18-40 years; between 37-42 weeks of gestation; no complications of pregnancy; fetal health without malformation; voluntarily sign the informed consent to cooperate in examinations. Exclusion criteria: aged under 18 years or elderly parturient women over 40 years; complications during pregnancy; prenatal examination clearly indicated fetal malformation; puerperal with incomplete clinical data. The self-comparison was used in the study, the details of puerpera are shown in Table 1 and this study has been approved by the Ethics Committee of the Affiliated Hospital of North Sichuan Medical College.
Fulfilled by the same senior ultrasound physician with over 5 years’ work experience, the fetus weight was estimated by using clinically used two-parameter formula (fundal height and abdominal circumference) and GE-E10 four-dimensional color ultrasound multi-parameter (fetal biparietal diameter, head circumference, abdominal circumference and femur length) for all puerperal one week before delivery.
That is, the professional physician of obstetrics department will examine puerpera in terms of conventional measurement parameters: uterine height, abdominal circumference and abdominal wall thickness; Each index was measured twice, with the mean value as the final result, and the estimated fetal weight was calculated as = uterine height × abdominal circumference +200g.
GE-E10 Four-dimensional Color ultrasound Multi-parameter
The equipment is American GE-E10 four-dimensional color ultrasound diagnostic device, with the probe frequency of 3.5 MHz. Ultrasound probes were used to continuously track the head, face, neck, chest, abdomen, spine, limb structure, placenta and amniotic fluid of the fetus, lengthways, horizontally and slantly. Detailed measurement parameters: fetal biparietal diameter, head circumference, abdominal circumference, length of femur and etc.; Each index was measured for three times, and the average value was taken as the final result. The data were through post-processing by relevant software of ultrasonic obstetrics to calculate the estimated fetal weight.
The puerperal were tracked till delivery, the birth weight of fetus was taken as the gold standard. The error was ±10g with the electronic newborn scale in the operating room. The accuracy of the two methods in estimating fetal weight and the coincidence rate in predicting macrosomia were compared and analyzed, and the calculated error ±200g was considered to be accurate or consistent. Macrosomia refers to the weight of a newborn being more than or equal to 4000g within 1 hour after birth. The ROC curve charts of the two estimation methods were drawn to evaluate their application efficacy (sensitivity and specificity).
All data involving the study were analyzed and processed through the statistical software SPSS 20.0. The measurement data were expressed as mean ± standard deviation (' x±s). The counting data were expressed as a percentage (%), and Chi-square test was used between groups. P<0.05 was considered statistically significant.