The biophysical profile in labor.

ABSTRACT

To determine whether the biophysical profile would be a valuable intrapartum addition to fetal heart rate monitoring in predicting umbilical arterial acid-base status at delivery, 95 patients at term had serial studies during labor and umbilical artery blood gas analysis. There was no significant association between biophysical profile score and cord blood pH, nor was there a difference in scores between the acidemic and nonacidemic groups. Of the five components of the initial biophysical profile, only a nonreactive nonstress test (NST) was associated with both pH 7.20 or less (P = .019) and metabolic acidemia (P = .016). None of the individual variables of the final examination correlated with a pH of 7.20 or less. However, a nonreactive NST was associated with metabolic acidemia (P = .03), as was the presence of breathing (P = .03). Of the ten infants with pH 7.20 or less, eight had an initial and five had a final biophysical profile score of 8 or higher. Of the five whose pH was less than 7.15, four had an initial and three a final score of 8 or more. Finally, of the five with metabolic acidemia, four had an initial and two a final score of 8 or higher. Half of the acidemic fetuses had final biophysical profile scores of 8 or higher, suggesting that this score in labor is not reliable to rule out acidemia at delivery.(ABSTRACT TRUNCATED AT 250 WORDS)