Maternity care specialists are still looking for ways to properly anticipate fetal weight in order to reduce the negative consequences associated with traumatic birth. The goal of this study is to see whether assessing umbilical cord thickness, interventricular septum thickness, and HbA1c may help predict fetal macrosomia in gestational diabetes patients. This is prospective case-control research that took place between March 2020 and October 2021 on 80 pregnant women with a gestation of 36 to 37 weeks who visited Al Zahra'a Hospital, Al-Azhar University. After the local hospital ethics and research council accepted the study, the patients were separated into two groups: 40 diabetes pregnant women and 40 non-diabetic pregnant women. The diameter of the umbilical cord was  recorded using ultrasound technology. Using ultrasound machine software, the umbilical arteries and veins were measured in a free loop of the umbilical cord. The cross-sectional area of Wharton's jelly was calculated by subtracting the cross-sectional area of the vessels from that of the umbilical cord and the interventricular septum thickness was measured. The HbA1c level was determined. The mean of umbilical cord thickness of study group was (21.55 ± 4.73), umbilical vein (8.85 ± 2.16), umbilical artery (5.18 ± 1.36), Wharton's jelly (54.75 ± 15.85), IVS thickness (5.63 ± 1.55) and HbA1c (6.5 ±0.92). They had highly statistically significant difference (P=0.00) in diabetic group than control group were linked to fetal macrosomia. Using a ROC curve to assess their prediction performance for macrosomia detection, the ideal HbA1c cut-off point > 5.6 percent, with a sensitivity of 100% and a specificity of 68.25 percent (AUC 0.92; p <  0.00).Umbilical cord thickness  cut-off point > 21.5) where the sensitivity was100 % and the specificity was( 100%), (AUC 1.00; p < 0.00) and IVS thickness  cut-off point >4.9 where the sensitivity was100 % and the specificity was74.6% (AUC 0.921; p < 0.00). The Apgar score of the neonates of study group at (1,5&10) minute was significantly lower than the control group(P=0.00). There was a significant very strong positive correlation(r=0.850) between NICU duration of admission and IVS thickness (P=0.00). In individuals with gestational diabetes, ultrasound measures the diameters of the fetal umbilical cord and interventricular septum thickness, together with HbA1c levels, may help predict fetal macrosomia. Our research found a substantial very strong positive association between interventricular septum thickness and length of stay in the NICU.