My wife has pulmonary embolism from birth control she's 40 years old it's been 3 weeks and she still can't catch her breath how long should it take to start exercising .?

Treated?: Has she seen the doctor and us she being treated? This is imperative! this is a life threatening problem. The breathing difficulties can persist but she needs careful attention and monitoring of treatment. The doctor will assess the timing for exercise tolerance with your wife.

Depends: It depends on how much of your circulation was blocked by the pulmonary emboli and varies too with your cardiac and lung function before the event. It can take a month or two for a pe to resolve with anticoagulation and not all resolve completely. If shortness of breath persists longer than this then a doctor eval is required.