There is provided an apparatus (12) for use with a wearable cuff (14) in measuring blood pressure. The cuff (14) is inflatable to pressurize a measurement site (20) of a subject (18). The apparatus (12) is configured to estimate a size of the cuff (14) during a current inflation of the cuff (14) and compare the estimated size of the cuff (14) to a previous size of the cuff (14) estimated during an inflation of the cuff (14) that immediately preceded the current inflation of the cuff (14). The apparatus (12) is also configured to, if the estimated size of the cuff (14) differs from the previous size of the cuff (14) by more than a predefined amount, change a pressure up to which the cuff (14) is inflated before deflation of the cuff (14) starts.