An OCT-reactivity classification to predict fetal outcome.

Based on analyses of the oxytocin challenge test (OCT) in 293 cases, an OCT-reactivity classification is proposed to improve the predictive value of OCT for fetal outcome. All of the 6 perinatal deaths occurred in the 2 groups associated with nonreactive pattern. The positive nonreactive test had 90% accuracy of predicting a sick infant, and the negative reactive test assured good fetal outcome. A nonreactive pattern seems to reflect a compromised fetus, as a high incidence of this pattern was found in patients with pre-eclampsia-hypertension, intrauterine growth retardation (IUGR), low and falling estriol levels, and suspected fetal problems. A positive OCT seems to reflect the limits of fetoplacental reserve under the stressed condition. A high incidence of positive OCT was associated with IUGR, low estriol levels, and a small placenta.