Most preterm births occur after natural or unintended delivery (as opposed to medically necessary preterm birth, which refers to delivering the fetus as quickly as possible to protect the mother and fetus). Predicting who will have risk factors for prenatal pain is difficult. But some women with risk factors did not experience labor pains, while other women with unknown risk factors experienced labor pains before their due date. About half of the women who have been confirmed by professional doctors to have normal prepartum uterine contractions (no premature rupture of membranes before 37 weeks) will definitely need assisted delivery throughout the delivery process. Most premature births occur naturally or unexpectedly