Copeptin has been shown to be associated with central nervous system pathologies. The aim of this study was to investigate the relationship between serum CCP levels and central nervous system (CNS) anomalies. In this case-control study, those at 9–14 weeks of gestation serum levels of copeptin, were assessed in pregnant women whose foetuses subsequently developed CNS anomalies (group 1: n = 60) and compared with gestational age-matched pregnant women who exhibited normal pregnancy outcomes (group 2: n = 48). The mean copeptin levels were 1.58 ± 0.40 ng/mL and 1.11 ± 0.36 ng/mL in the CNS anomalies and control groups, respectively (p < .0001). An increased level of copeptin independently predicts development of CNS anomalies, suggesting that copeptin can be used for prediction and discrimination of CNS anomalies in normal pregnancies at 9–14 weeks of gestation. Impact statement What is already known on this subject? There is no test or method to diagnose CNS anomalies in the first trimester of pregnancy. This study presents the first and new information on the relationship between serum copeptin levels and central nervous system anomalies in pregnant women whose foetuses subsequently developed CNS anomalies. What do the results of this study add? I have strongly demonstrated differences in maternal CPP levels between CNS anomalous pregnancies and healthy controls. What are the implications of these findings for clinical practice and/or further research? It has been thought that copeptin appears to be an ideal marker for central nervous system anomaly prediction at 9–14 weeks of gestational age and if confirmed in larger prospective studies. Finally, these results could not be used as parameters for prenatal CNS screening. Advanced studies, well-structured and conducted on larger populations are needed to investigate the issue further.