Longitudinal Variance of Fat Mass Deposition during Pregnancy Evaluated by Ultrasonography: The Ratio of Visceral Fat to Subcutaneous Fat in the Abdomen

BACKGROUND: Defining regional fat distribution is of importance because of regional variation in adipocyte metabolism. In order to investigate whether maternal body fat distribution changes during pregnancy we measured the abdominal maternal fat thickness. METHODS: A longitudinal study of the thickness of the preperitoneal fat layer (P) and subcutaneous fat layer (S) in the abdomen was conducted; ultrasonography was used to obtain the measurements and the P/S ratio was calculated during each trimester as well as postpartum. RESULTS: When compared with the first and second trimesters, a significant increase in both the P and P/S ratios was observed in the third trimester; thus, regional fat distribution changes during pregnancy. CONCLUSION: Intra-abdominal visceral fat accumulation increases during pregnancy.