Placental phosphatase of maternal serum: relationship to pregravid weight, prenatal weight gain, and infant birthweight in normal human pregnancies

Abstract
Serum placental phosphatase (heat-stable alkaline phosphatase, HSAP) was measured in the following gravidae with normal weight gain: 71 normal weight normal subjects (NWN), 26 overweight normal subjects (OWN), and 28 underweight normal subjects (UWN); and in the following gravidae with excess gain (XsG), small gain (SmG), or weight loss (WtL): 11 NWN·XsG, seven NWN·SmG, seven OWN·SmG, two OWN·XsG, three OWN·WtL, and five UWN·XsG. The NWN regression equation between 31 and 40 weeks was: Y = 0.6X – 18.44. Overweight subjects' HSAP values were typically below and underweight subjects' values were above the regression line, providing that the weight gain was not less than normal in the overweight group or greater than normal in the underweight group. The average difference from the NWN regression line for each subject was designated “Δ HSAP.” The difference between the mean Δ HSAP values was statistically significant for: NWN versus OWN, NWN versus UWN, OWN versus UWN, NWN·XsG versus NWN·SmG, NWN versus NWN·SmG, NWN versus NWN·XsG, and OWN versus OWN·WtL. The higher Δ HSAP values were associated with relative caloric insufficiency, the lower values with relative caloric excess. A low degree of inverse correlation was found between infant birthweight and Δ HSAP (r = −0.37; P < 0.002).

This publication has 14 references indexed in Scilit: