ESPE Abstracts

Background and aim: Pregnancy with diabetes mellitus is associated with obstetric and neonatal complications, including the development of fetal macrosomia. Fetal macrosomia of diabetic origin is characterized by a disproportionate distribution of subcutaneous fat with predominant localization in the upper half of the fetus body. The cause of excess fetal growth is maternal hyperglycemia, regardless of the type of diabetes in the mother. The aim of study was to assess the possibility of diagnosing disproportionate development of a newborn according to antenatal measurements of fetal subcutaneous fat.

Material and Methods: A study included 76 pregnant women with diabetes mellitus. The inclusion criteria were as follows: singleton pregnancy, gestational age > 37weeks; the exclusion criteria: in vitro fertilization, fetal malformations, hemolytic disease and non-immune fetal hydrops. To assess the excess accumulation of fat mass in newborns, the anthropometric ratio (weight/length ratio (WLR)) was calculated and assessed by sex and gestational age (calculator for WLR INTERGROWTH-21st). Groups were formed: WLR by sex and gestational age less than 90 centile - group 1 (n=46), WLR by sex and gestational age equal to 90 centile and more - group 2 (n=30).

Results: Fetuses from mothers with diabetes mellitus are characterized by a more significant accumulation of subcutaneous fat in the upper half of the body, which correlates with the WLR by gestational age and sex: fetal sub-scapular fat mass and WLR rs=0.76, P<0.001, fetal abdominal fat mass and WLR rs=0.85, P<0.001, fetal mid-thigh fat mass and WLR rs=0.77, P<0.001. The calculated cut-off values of fetal subcutaneous fat (fetal sub-scapular fat mass 5.8 mm or more (AUC 0.93 (0.86-0.99), P<0.001), fetal abdominal fat 5.8 mm or more (AUC 0.97 (0.93-1.00), P<0.001), fetal mid-thigh fat mass 4.4 mm or more (AUC 0.94 (0.87-0.99), P<0.001) with high specificity (95.7%, 91.3% and 87.0%) and sensitivity (73.3%, 93.3% and 93.3%) allow antenatal diagnosis of disproportionate fetal development in women with diabetes mellitus.

Conclusion: The study of fetal subcutaneous fat is an important step in the diagnosis of fetal macrosomia.