Normal maternal body composition values for the first trimester of pregnancy.

Objective: Body composition is a key determinant of fetal and maternal health. The objective of this study was to develop normal values for maternal body composition in the first trimester of pregnancy using advanced bioelectrical impedance analysis (BIA). Methods: Women were enrolled in the first trimester after a sonogram confirmed their dates and an ongoing singleton pregnancy. The study was confined to healthy Caucasian women. Height and weight were measured digitally, and BMI calculated. Body composition was analysed using advanced BIA (Tanita, MC 180). Results: Of the 1000 women studied, the mean BMI was 25.7 kg/m2 (SD 5.3) and the mean weight was 69.1 kg (SD 14.7). Of the mean weight, 22.7 kg was fat and 46.5 kg was fat-free. On average, the arm fat was 2.6 kg, leg fat 9.5 kg and trunk fat 10.6 kg. The mean, median, standard deviation, 10th and 90th centile for all body composition parameters are reported. The measurements were also analysed by age and parity. Conclusions: The establishment of these normal values will facilitate comparisons with other ethnic groups and will provide a baseline for longitudinal studies during pregnancy and following pregnancy. It will also facilitate comparisons between BIA and other measures of body composition as predictors of clinical outcomes. [ABSTRACT FROM AUTHOR]