Advantages of vaginal delivery.

Despite an impressive amount of effort and extensive research, our knowledge of parturition remains limited. Scientists have exhaustively investigated ‘‘the timing of birth’’; yet, we still have a limited understanding of the biologic mechanisms that control the events initiating delivery, and consequently, we lack tools to prevent these mechanisms from acting inappropriately. A multitude of factors and structures are involved; the uterus, the cervix, the placenta, and the fetus must all act in concert to ensure a successful delivery. We know that achievement of ‘‘perfect’’ myometrial contractile force to produce cervical dilatation is not the sole factor. Successful delivery also depends on pelvic shape and size as well as fetal size. Birth is perhaps the most exciting and risky journey taken over a lifetime. For many years, labor was simplistically regarded as the physiological process of expelling the fetus from the ‘‘womb’’ at or near term. Today, terms such as ‘‘labor’’ and ‘‘successful vaginal delivery’’ have a different meaning for many who have concentrated their attention onmaternal and fetal shortor long-term outcomes of a successful or unsuccessful vaginal birth, but also for the ones who have witnessed the evolution of obstetric ‘‘fashion.’’ Rational arguments have imposed a clear distinction between ‘‘facts’’ and ‘‘convenience.’’ Practice changes as knowledge progresses. One of the changes witnessed in the last decades is a steadily increasing focus on the fetus. Thus, it is not surprising to see that the overall rate of labor induction has doubled as part of our efforts to ‘‘save life.’’ Although there is compelling evidence to suggest elective induction of labor significantly increases the risk of cesarean delivery (CD), the concept of elective primary cesarean section is not anymore a ‘‘myth.’’ Powerful debate is taking place in obstetrics regarding the benefit of cesarean over vaginal delivery. Several lessons can be learned from this controversy, and skepticism must be countered only by solid lines of evidence. The purpose of this review is to provide the reader with a summary of our current understanding of the advantages of vaginal delivery.