There are many reasons you might miss a period. Simple things such as stress or exercising too much can cause a missed period and many girls are irregular during the first few years of menstruating. But if you've missed a few periods, be sure to see your healthcare provider.
Courts usually find probable cause when there is a reasonable basis for believing that a crime may have been committed (for an arrest) or when evidence of the crime is present in the place to be searched (for a search).
cause. 1. a person that acts or a thing that occurs so as to produce a specific result: the cause of the accident. 2. the reason or motive for some action: a cause for rejoicing. 3. good or sufficient reason: to complain without cause.