Caesarean section is a common abdominal operation for surgical delivery of a baby and the placenta. Techniques vary depending on the clinical situation and surgeon preferences. Safe delivery is important for mother and infant. Any potential reduction of birth trauma to the infant has to be balanced against increased ill-health for the mother. Factors include not only the duration of the surgical procedure and maternal blood loss but also maternal postoperative pain, continuing blood loss and development of anaemia, fever and wound infection. Additional complications can include problems with breastfeeding, passing urine, longer-term fertility problems, and complications in future pregnancies (uterine rupture) or increased risks associated with future surgery.
The review authors searched the medical literature for randomised controlled trials to inform the most appropriate surgical techniques to use. Twenty-seven trials involving 17,808 women from a number of different countries contributed to the review. None of these trials assessed the type of uterine incision (side to side (transverse) lower uterine segment incision versus other types of uterine incision). Results from 18 randomised trials contributed to reports that single layer closure of the uterine incision was associated with a reduction in blood loss, and duration of the procedure. In these studies the surgical procedure for entering the abdominal cavity also differed and could have contributed to blood loss and duration of surgery.
Five trials compared blunt with sharp dissection at the time of the uterine incision (2141 women) and a further two trials auto-suture devices with standard hysterotomy (300 women). Blunt surgery was associated with a reduction in mean blood loss at the time of the procedure. The use of an auto-suture instrument did not clearly reduce procedural blood loss but increased the duration of the procedure. Overall, trials focused on blood loss and duration of the operative procedure rather than clinical outcomes for the women. The methodological quality of the trials was variable.