Correlation of nonstressed fetal heart rate with sequential contraction stress test

Two hundred seven high-risk patients were studied prospectively by standardized nonstressed fetal heart rate monitoring followed immediately by contraction stress testing (CST). Of the 604 combined procedures examined, 90.2% of nonstress tests (NST) were interpreted as reactive; none was associated with a positive CST. Of the nonreactive NSTs, 37% were followed by positive CSTs. These data support the contention that a reactive NST performed in compliance with a standard protocol is unlikely to be associated with a positive CST.