Seventy percent of Cesarian sections are indicated by a failure to progress, a non-reassuring fetal heart rate (FHR), a previous Cesarian section, or fetal malpresentation (breech or transverse positions). Other indications (the other 30%) are abnormal placentation (placenta previa or vasa previa), mechanical obstruction (such as with a fibroid or teratoma), maternal infection (e.g., herpes or HIV), multiple gestations, cervical cancer, or fetal congenital anomalies.
There are two main techniques for performing a Cesarian section: vertical and Pfannensteil. The vertical technique is faster, with less blood loss. It is used in emergency situations, in patients who are obese, have previous scars, or are bleeding abnormally. The Pfannensteil technique involves a low transverse incision. Because it cuts along Langer's lines, it is more cosmetic, and theorized to be less stressful. The Pfannensteil is usually the standard for most Cesarian sections.