Prevalence of Nonreactive Non-Stress Test in Low Versus High Risk Pregnancy
Integrative Gynecology and Obstetrics Journal
Objective: To determine the prevalence of non-reactive non-stress test (NST) in low risk and high risk pregnant women. Materials and Methods: This prospective cohort study enrolled pregnant women with gestational age of 32 weeks or more who had been offered NST by their obstetricians at the antenatal clinic, King Chulalongkorn Memorial Hospital. High risk group were defined as having any maternal, fetal or placental risk factors. The NST result was interpreted by at least two obstetricians. All
... participants were followed until delivery and perinatal outcomes were recorded. Results: A total number of 1,168 participants with 1,261 NST tests were included. 782 tests (62%) were offered to low risk and 479 tests (38%) to high risk group. Decrease in weight and maternal diabetes mellitus was the most common indication for low risk and high risk group, respectively. Overall prevalence of non-reactive NST was 0.32% (0.38% in low risk and 0.21% in high risk group). Only one newborn with non-reactive NST in high risk group was admitted in the NICU due to meconium aspiration syndrome. However, there was no significant association between non-reactive NST and obstetric risks or adverse perinatal outcomes. Conclusion: The prevalence of non-reactive NST in this study was only 0.32%. NST is not routinely recommended in low risk pregnant women due to no association between non-reactive NST and perinatal morbidity.