OBJECTIVE: To determine the effect of exercise stress test (EST) through brisk walking on the cardiotocogram tracings (CTGs) and the association of the tracings to neonatal outcomes.

METHODOLOGY: This one-group pretest-post test experimental study involved 65 term pregnant women (mean age = 25.94 + 4.66 years) who underwent brisk walking exercise using a motorized treadmill for 30 minutes, following American College of Obstetricians and Gynecologists (ACOG) guidelines for exercise among pregnant women. Pre- and post- walk CTGs were assessed, with presence of post-walk decelerations taken to mean a positive EST. Sensitivity (positive EST in sick / meconium-stained / cord coil babies), specificity (negative EST in well babies), positive predictive value (PPV) (probability of sick / meconium-stained / cord coil babies given positive EST) and negative predictive value (NPV) (probability of well babies given negative EST) were computed.

RESULTS: A significant difference in the proportion of subjects with pre- and post- walk decelerations was noted (p-value = 0.000) wherein 18 subjects (28.13%) without decelerations in the baseline CTG had decelerations in the post-walk CTG. These decelerations were significantly associated to having sick, meconium-stained, or cord coil babies (p-values < 0.05). EST had 80% sensitivity, 75% specificity, 21.1% PPV and 97.8% NPV for detecting sick babies; 75% sensitivity, 77.2% specificity, 31.6% PPV and 95.7% NPV for detecting meconium-stained babies; and 75% sensitivity, 85.7% specificity, 63.2% PPV and 91.3% NPV for detecting nuchal cord.

CONCLUSION: Exercise stress testing is a complementary way of assessing fetal well-being due to manifestation of decelerations in the post-walk CTG which could have gone undetected if only the resting CTG was done. The EST had high sensitivity for detecting sick / meconium-stained / cord coil babies and has the advantage of reinforcing a reassuring fetal condition due to its high NPV for detecting well babies.