Oxytocin challenge test.

This study reviews the indications, interpretation, and practical application of the oxytocin challenge test (OCT) in 154 patients undergoing 375 tests. It emphasizes aspects of technique which may make the "challenge" nonphysiologic and the stress, therefore, nonquantifiable. Thirty-four positive or suspicious tests were obtained in 22 patients. These results are correlated with clinical complications of pregnancy; antepartum indices of fetal well-being (estriol, ultrasonic serial cephalometry, and the presence of meconium on amniocentesis); and subsequent intrapartum fetal heart rate response. Unsatisfactory (47 in 23 patients), false-positive, and false-negative tests are reviewed in detail. Since false-positive tests (47.9 per cent) are common whereas false-negative tests are rare (2.8 per cent), we conclude that the negative test is a reliable indication in high-risk pregnancies. Positive tests add to out data on the fetus and alert us to the need for a totally monitored labor.