Babies love being unpredictable. If there were a way to induce labor through drinking tea, exercise, sex, or some other magic, we would tell you. Like eating dates, there are dozens of such claims and the reason so many fibs exist is simple: women eventually go into labor and sometimes they will falsely contribute whatever they did immediately prior to labor as the reason things got going. The stronger the correlation of the timing between the onset of labor and the thing they did, the stronger the belief. But actually the body just does what it is going to do on its own terms. Unless you go into labor spontaneously, the only thing we can do to induce its onset is medication.