The Role of Umbilical Cord Thickness in Prediction of Fetal Macrosomia in Patients With Gestational Diabetes Mellitus

This prospective case control study will be carried out at Ain shams university maternity hospital between April 2015 and October 2015 on 80 patients. The patients will be divided into two groups, 40 pregnant women as case group with gestational diabetes mellitus and 40 non diabetic pregnant women as control group after being approved by the local hospital ethics and research committee. A verbal consent will be taken from each patient.

The following investigation will be performed:

• Calculation of gestational age will be based on the last reliable menstrual period or ultrasound examination within the first trimester.

The ultrasound examination will be with Voluson E6 equipped with a 3.5 Hz trans-abdominal probe at fetal medicine unit of maternity hospital Ain Shams University.

• Ultrasound examination will be performed twice at 27-28 weeks and 36-37 weeks of gestation prospectively.

During ultrasound, fetal biometry (biparietal diameter, abdominal circumference, femur length) and estimated fetal weight will be calculated automatically according to hadlock's formula additionally, the sonographic cross sectional area of umbilical cord, the umbilical arteries and umbilical vein will be measured in a free loop of the umbilical cord using the software of the ultrasound device.

The cross sectional area of Wharton's jelly will be computed by subtracting the cross sectional area of the vessels from that of the umbilical cord and the interventricular septum thickness will be measured.

• HbA1c levels will be measured for diabetes patients.

All the patients will be subjected to :

• Full history taking including last menstrual period, medical history and past obstetric history.
• Detailed general physical history examination and obstetrics examination.
• Ultrasound examination in fetal medicine unit maternity hospital Ain shams university.
• Venous blood samples will be taken from patients with gestational diabetes mellitus in clinical pathology department Ain Shams University, to measure the level of HbA1c using immunoassay technique. The patients will be followed up till delivery. The neonates will be weighed and fetal macrosomia will be diagnosed if fetal weight is 4 kg or more.

Inclusion criteria

• Singleton gestation.
• Gestational age over 27 weeks.
• Intact membranes.
• Normal umbilical morphology (two arteries and one vein).
• Diagnosis of gestational diabetes.

Exclusion criteria

• The presence of fetal congenital anomalies.
• Multifetal pregnancy.
• Maternal chronic diseases (hypertension, renal disease, cardiac and pulmonary disease, etc.).
• Patients with a diagnosis such as oligohydramnios , pre-eclampsia and intrauterine growth retardation.
• Patients who used cigarettes or alcohol during pregnancy.