Comparison of five-site skinfold thicknesses in late pregnancy vs early postpartum.

To test the hypothesis that the sum (∑) of five skinfold thicknesses in the immediate postpartum period is significantly less than that obtained in the last month of pregnancy in healthy American women, a standardized approach was used to measure skinfold thicknesses at five sites in 81 healthy, active women. Measures were obtained in the last month of pregnancy and again in the first month postpartum. Prior to pregnancy the subjects ranged in age from 24-39 years and weighed between 45-87 kg. The ∑ of five skinfold thicknesses ranged between 34 and 162 mm. During pregnancy, weight gain ranged between 6.5-24.6 kg with a mean gain of 14.5 kg. The ∑ of five skinfold thicknesses peaked between 8-36 weeks gestation and the peak increase ranged from -19 mm to +63 mm above preconceptual levels. In late pregnancy, the ∑ of five skinfold thicknesses ranged between 34.1 and 166.8 mm (mean = 91.7 mm), and postpartum, the range and mean values were similar (38.1-156.4 mm, and 91.8 mm). When values obtained in late pregnancy are compared with those obtained postpartum, the r value was 0.9122. There was also good correlation at each of the skinfold sites (r 's = 0.8001-0.9239), except the abdomen (r = 0.6049). In conclusion, the hypothesis is incorrect; the ∑ of five skinfold thicknesses in the immediate postpartum period is as acceptable a measure of late pregnancy subcutaneous fat deposition and/or retention as that obtained in the last month of pregnancy in present day healthy American women. Am. J Hum. Biol. 10:299-305, 1998. © 1998 Wiley-Liss, Inc.