Relationship between sonographically estimated fetal subcutaneous adipose tissue measurements and neonatal skinfold measurements.

Objective: Increased subcutaneous adipose tissue is a well known characteristic of diabetic fetopathy. Prenatal estimation of adipose tissue can be performed by ultrasound, while postnatally skinfold measurements are performed using a Holtain caliper. The aim of this study was to compare these methods in the same patients.

Methods: This was a prospective study of 172 pregnant patients (142 controls and 30 with gestational diabetes) at ≥ 37 gestational weeks. In addition to fetal weight estimation, fetal subcutaneous tissue was measured at the anterior abdomen lateral to the umbilicus (SonoSfAbd) and at the middle of the femur (SonoSfFem). Within 72 h after delivery, a Holtain caliper was used to measure neonatal skinfold thickness at the left anterior iliac spine (SfAbd), at the lower angle of the left scapula (SfSca), at the middle of the femur, above the left quadriceps femoris (SfFem) and at the middle of the left triceps (SfHum). Ultrasound and mechanical measurements were correlated.

Results: The sonographic and mechanical methods showed good correlation with each other. Linear regression analysis gave the following equations: SfAbd (mm) = SonoSfAbd (mm) × 0.489 + 1.988 (r(2) = 0.34, P < 0.001); SfSca (mm) = SonoSfAbd (mm) 0.457 + 2.043 (r(2) = 0.40, P < 0.001); SfFem (mm) = SonoSfFem (mm) × 0.714 + 1.763 (r(2) = 0.41, P < 0.001); SfHum (mm) = SonoSfFem (mm) 0.564 + 2.09 (r(2) = 0.39, P < 0.001).

Conclusions: Ultrasound examination is a reliable method for non-invasive intrauterine measurement of fetal subcutaneous tissue and can be used to predict mechanical neonatal skinfold thickness measurements.