Depends on situation. In an emergency situation where the baby may be in distress, general anesthesia with intubation is often the fastest and most reliable choice. For an elective or less urgent csection, epidural or spinal anesthesia is preferred. Less medication reaches the baby, and the mother can be awake to see her baby right away. Talk to your anesthesiologist about anesthesia options for labor and delivery.
Spinal/epidural best. Epidural or spinal (i.e. Regional) anesthesia is by far preferable to general endotracheal anesthesia for cesarean sections. Exceptions to this rule: stat/emergency cesarean, low platelet count in the mother, spinal anomalies/deformities.
Prefer epidural. As the pregnant patient is at risk for aspiration of stomach contents in the face of general anesthesia, we prefer to administer an anesthetic where the patient can control airway reflexes. Also, many perspective moms prefer to be awake. A general can be safely performed however, if necessary.