1 st trial of nomograms for fetal cardiac measurements between 14 and 36 weeks of gestation in the north-eastern Egyptian population (Qalyubiyya Governorate)

Abstract Objective It is important to define the normal growth patterns of the fetal cardiovascular structures during early period of fetal life, and this can aid in early detection of subtle abnormalities of cardiac anatomy. Accurate measurement of fetal cardiac dimensions is essential to assess the patterns of cardiac remodeling. These measurements help in understanding and monitoring fetal adaptation to adverse environments, thereby contributing to better prenatal care and outcomes. There is shortage in studies looking at measurements of normal cardiac anatomical dimensions, especially among the Egyptian population. This study aimed to provide GA-specific reference ranges and nomograms for fetal cardiac dimensions in the 2nd and 3rd trimesters among the Egyptian population using a well-defined two-dimensional echocardiographic examination in a low-risk population. Methods This cross-sectional study was conducted on a total of 900 healthy pregnant women who attended the Ultrasound unit at Benha University Hospital for routine antenatal scan, with singleton pregnancies of normal fetuses with varying gestational ages from 14 + 6th to 36 + 6th weeks of gestation. Measurements included the cardiac circumference (CC) and thoracic circumference (TC), the inner diameters of the fetal cardiac chambers, the foramen ovale diameter, myocardial wall and interventricular septal thickness, the diameters of the atrioventricular valve rings, the arterial roots diameters, the great vessels diameters, and transverse ductus arteriosus diameter. Measurements were statistically analyzed; normal reference values of the obtained fetal cardiac dimensions were constructed; regression analysis was applied in correlation with gestational age, and regression equations were provided. Results The study presented normal ranges of fetal cardiac dimensions week by week from the 14 + 6th to the 36 + 6th week of gestation. All measurements were non-normally distributed. All cardiac dimensions showed progressive increase with gestational age. Linear, cubic, quadratic, and exponential statistical models were used to assess the relationship between cardiac measurements and gestational age ( p value < 0.001). The r 2 values of the used regression models were very close, however we found that the quadratic regression model was the best fitted for most of cardiac dimensions. Centile graphs and nomograms were also constructed for fetal cardiac dimensions. Conclusions We provided reference ranges, regression equations, centile graphs, and nomograms for various fetal echocardiographic measurements in low-risk singleton pregnancies among north-eastern Egyptian Population (Qalyubiyya Governorate). To our knowledge, our study was the first trial to construct normal reference ranges of fetal cardiac dimensions of governmental nomograms, providing an essential baseline data that enhances the early identification of different patterns of fetal cardiac remodeling.