Relationship Between Combined Fetal Biophysical Activities, Oligohydramnios, and Fetal Acid–Base Status

Abstract

The purpose of this study was to determine the relationship between combined fetal biophysical activities, oligohydramnios, and fetal acid-base status at the time of testing. In a prospective study of 101 patients undergoing cesarean section before the onset of labor, a fetal biophysical profile was performed within 3 h before the cesarean section. Different combinations of fetal biophysical activities (fetal heart rate reactivity, fetal breathing movements, fetal body movements, and fetal tone) and oligohydramnios were correlated with umbilical cord blood gas and acid-base measurements (artery and vein). Fetal acidemia was defined as umbilical arterial blood pH <7.20. The group of fetuses with reactive nonstress test (NST) and/or fetal breathing present had significantly higher pH, pO2, bicarbonate, and base excess and significantly lower pCO2 levels compared with fetuses who had nonreactive NST, absent fetal breathing, and compromised or absent body movements and tone. These blood gas and acid-base diff...