Monitoring physical activity and rumination time in the early postpartum period could be effective for detecting cows with metabolic and digestive issues. There are significant changes in rumination time and activity pattern 1-day prepartum but still, it’s quite hard to predict calving time based on these patterns. It can be helpful if proper insemination and pregnancy diagnosis record is available. The Health index score developed by the AHMS based on rumination and activity had a high sensitivity for detecting metabolic and activity issues in cows, and it detected hypocalcemia and lameness earlier than Clinical diagnosis by farm employees. From -5 to 5 days following a clinical diagnosis of the disease of interest, sick cows showed considerable changes in rumination, activity, and HIS compared to cows in the healthy group as early as 5 days before CD, with a nadir around CD timing (-1 to 1 day after CD).