BACKGROUND: Healthcare interventions are shaped by the resources needed to implement them, including staff time. This study, part of a process evaluation, aims to compare time spent on antenatal care (ANC) and related recordkeeping in two rural primary-level health facilities in Nepal, before and after implementation of an electronic decision support system intervention to improve ANC quality that required additional electronic documentation. METHODS: The study is a before-and-after, observational time-motion assessment. Researchers used the WOMBAT (Work Observation Method By Activity Timing) software to observe and record activities performed by auxiliary nurse midwives providing ANC in two rounds of data collection. We summed the observation time (in minutes) spent on activity categories for each day of observation, in each round of data collection. For each auxiliary nurse midwife, we estimated the proportion of total observation time spent on activities and compared these proportions before and after intervention implementation. We also compared the mean minutes per day spent on ANC and recordkeeping in the two rounds. RESULTS: Six auxiliary nurse midwives were observed over two data collection rounds (41 total observation days). Prior to intervention, providers spent 7% of their workday on ANC and 6% on related recordkeeping, and time spent on these activities did not change after intervention implementation. Only one of the six auxiliary nurse midwives demonstrated a statistically significant increase in time spent on ANC and recordkeeping after implementation. There was considerable day-to-day variation in ANC time, and substantial periods of "non-work" time (on break or not engaged in work-related activity). Non-work time reduced from 42% in the first round to 26% in the second round of data collection. CONCLUSIONS: Time spent on ANC and related recordkeeping was low and did not change after implementation of the electronic decision support system. ANC and recordkeeping time was sensitive to day-to-day fluctuations in numbers of women attending for ANC at these rural facilities, which may have masked the intervention's effects. However, the large amount of non-work time observed suggests time constraints during the workday were not a major factor inhibiting use of the electronic decision support system.