Caesarean section, also known as C-section, is the use of surgery to deliver one or more babies. A Caesarean section is often performed when a vaginal delivery would put the baby or mother at risk. This may include obstructed labour, twin pregnancy, high blood pressure in the mother, breech birth, problems with the placenta, umbilical cord or shape of the pelvis, and previous C-section. A trial of vaginal birth in some of these situations, including after C-section, may be possible. Some C-sections are also performed upon request. The World Health Organization recommends that they should be done based on medical need and in many cases they are lifesaving for the mother and baby.

A C-section typically takes 45 minutes to an hour. It may be done with a spinal block such that the women is awake or under general anesthesia. A urinary catheter is used to drain the bladder and the skin of the abdomen is then sterilized. An incisions of about 15 cm (6 inches) is then typically made through the mother's lower abdomen. The uterus is then opened with a second incision and the baby delivered. The incisions are then stitched closed. A women can typically begin breastfeeding as soon as she is awake and out of the operating room. Often a number of days are required in hospital to recover sufficiently to go home.

Caesarean section is recommended when vaginal delivery might pose a risk to the mother or baby. C-sections are also carried out for personal and social reasons. Systematic reviews have found no strong evidence about the impact of caesareans for non-medical reasons. Recommendations encourage counseling to identify the reasons for the request, addressing anxieties and information, and encouraging vaginal birth. Elective caesareans at 38 weeks showed increased health complications in the newborn. For this reason, planned caesarean sections (also known as elective caesarean sections) should not be scheduled before 39 weeks gestation unless there is medical reason to do so.