Sir, We welcome the article on maternal heart rate (MHR) analysis during labor by van Veen et al. (1). Hopefully, this will bring more visibility to the important issue of misidentification of MHR during fetal heart rate (FHR) recording in labor and to new developments in computerized analysis that are underway (2, 3). Visual analysis of FHR tracings has been shown to be poorly reproducible (4) and it is possible that the same occurs with MHR tracings. Could this be an explanation for the finding reported by van Veen et al. of the occurrence of MHR decelerations during the first stage of labor, in contrast to the more well-known MHR accelerations during contractions and pushing, that we have consistently found with a system for computer analysis of MHR tracings, under development and validation by our group? In addition, computer analysis may provide a deeper understanding of the physiological basis of some MHR features during labour, by evaluating complex mathematical indices that have been shown to be associated with different maternal-fetal physiopathological conditions (2, 3).