A c-section, or cesarean section, is the delivery of a baby through a surgical incision in the mother’s abdomen and uterus. In certain circumstances, a c-section is scheduled in advance. In others, it’s done in response to an unforeseen complication.

According to the U.S. Centers for Disease Control, about 33 percent of American women who gave birth in 2011 had a cesarean delivery. (The c-section rate in the United States has risen nearly 60 percent since 1996.)Sometimes it’s clear that a woman will need a c-section even before she goes into labor. For example, you may require a planned c-section if:
You’ve had a previous cesarean with a “classical” vertical uterine incision (this is relatively rare) or more than one previous c-section. Both of these significantly increase the risk that your uterus will rupture during a vaginal delivery.
If you’ve had only one previous c-section with a horizontal uterine incision, you may be a good candidate for a vaginal birth after cesarean, or VBAC. (Note that the type of scar on your belly may not match the one on your uterus.)
You’ve had some other kind of invasive uterine surgery, such as a myomectomy (the surgical removal of fibroids).
You’re carrying more than one baby. (Some twins can be delivered vaginally, but most of the time higher-order multiples require a c-section.)