not really, sex can induce labor making your body have contractions, as far as how many time, well there is no nember, but trying wont hurt, but like it or or, the baby will come when he/she is ready to come meet the world.
It's possible, but only if you were pretty close to having it break already. The contractions caused by sex are not real contractions and won't bring on labor. What WILL help is that the male ejaculate can help to soften the cervix which is important for dilation. Good luck!