Aim: The aim of this study was to evaluate the prognostic value of normal and indeterminate patterns of cardiotocography in admission test (AT) and pregnancy outcome.
Material and methods: A prospective study enrolled 818 intrapartum singleton pregnancies with gestational age of >34 weeks, in the latent phase and with intact membrane. Cases were divided into the high- and low-risk groups. Non-Stress Test was interpreted according to the 2008 National Institute of Child Health and Human Development workshop. Adverse pregnancy outcomes were compared between groups based on AT interpretation.
Results: Out of 818 patients, 492 (60%) were categorized as low-risk and 326 (40%) as high-risk pregnancies. In low-risk patients, 410 (83.3%) had normal and 82 (16.7%) had indeterminate AT. These figures were 249 (76.4%) and 77 (23.6%) in high-risk patients, respectively, and two cases (0.6%) had abnormal AT. In both groups, thick meconium staining, non-reassuring fetal heart rate pattern, cesarean section and cesarean section due to non-reassuring fetal heart rate pattern were significantly more frequent in indeterminate AT than normal ones (P < 0.001). In high-risk pregnancies with indeterminate AT, the risk of low birthweight and neonatal intensive care unit (NICU) admission increased. The positive predictive value was less than 30% in predicting thick meconium staining, non-reassuring fetal heart rate pattern, PH ≤ 7.2 and NICU admission in both groups. Overall, negative predictive value of AT for neonatal death and NICU admission was 100% and 96%, respectively.
Conclusions: Indeterminate patterns of cardiotocography can predict adverse pregnancy outcomes and when facing this condition, obstetricians should act cautiously.