Caesarean section


Caesarean section, also known as C-section, cesarean, or caesarean delivery, is the surgical procedure by which one or more babies are delivered through an incision in the mother's abdomen. It is often performed because vaginal delivery would put the mother or child at risk. Reasons for the operation include, but are not limited to, obstructed labor, twin pregnancy, high blood pressure in the mother, breech birth, shoulder presentation, and problems with the placenta or umbilical cord. A caesarean delivery may be performed based upon the shape of the mother's pelvis or history of a previous C-section. A trial of vaginal birth after C-section may be possible. The World Health Organization recommends that caesarean section be performed only when medically necessary.
A C-section typically takes between 45 minutes to an hour to complete. It may be done with a spinal block, where the woman is awake, or under general anesthesia. A urinary catheter is used to drain the bladder, and the skin of the abdomen is then cleaned with an antiseptic. An incision of about 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 woman can typically begin breastfeeding as soon as she is out of the operating room and awake. Often, several days are required in the hospital to recover sufficiently to return home.
C-sections result in a small overall increase in poor outcomes in low-risk pregnancies. They also typically take about six weeks to heal from, longer than vaginal birth. The increased risks include breathing problems in the baby and amniotic fluid embolism and postpartum bleeding in the mother. Established guidelines recommend that caesarean sections not be used before 39 weeks of pregnancy without a medical reason. The method of delivery does not appear to affect subsequent sexual function.
In 2012, about 23 million C-sections were done globally. The international healthcare community has previously considered the rate of 10% and 15% ideal for caesarean sections. Some evidence finds a higher rate of 19% may result in better outcomes. More than 45 countries globally have C-section rates less than 7.5%, while more than 50 have rates greater than 27%. Efforts are being made to both improve access to and reduce the use of C-section. In the United States as of 2017, about 32% of deliveries are by C-section.
The surgery has been performed at least as far back as 715 BC following the death of the mother, with the baby occasionally surviving. A popular idea is that the Roman statesman Julius Caesar was born via caesarean section and is the namesake of the procedure, but if this is the true etymology, it is based on a misconception: until the modern era, C-sections seem to have been invariably fatal to the mother, and Caesar's mother Aurelia not only survived her son's birth but lived for nearly 50 years afterward. There are many ancient and medieval legends, oral histories, and historical records of laws about C-sections around the world, especially in Europe, the Middle East and Asia. The first recorded successful C-section was allegedly performed on a woman in Switzerland in 1500 by her husband, Jacob Nufer, though this was not recorded until 8 decades later. With the introduction of antiseptics and anesthetics in the 19th century, the survival of both the mother and baby, and thus the procedure, became significantly more common.

Uses

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 on maternal request in some countries.

Medical uses

Complications of labor and factors increasing the risk associated with vaginal delivery include:
Other complications of pregnancy, pre-existing conditions, and concomitant diseases, include:
Other
  • Decreasing experience of accoucheurs with the management of breech presentation. Although obstetricians and midwives are extensively trained in proper procedures for breech presentation deliveries using simulation mannequins, there is decreasing experience with actual vaginal breech delivery, which may increase the risk.

    Prevention

The prevalence of caesarean section is generally agreed to be higher than needed in many countries, and physicians are encouraged to actively lower the rate, as a caesarean rate higher than 10–15% is not associated with reductions in maternal or infant mortality rates, although some evidence support that a higher rate of 19% may result in better outcomes.
Some of these efforts include emphasizing a long latent phase of labor is not abnormal and not a justification for C-section; a new definition of the start of active labor from a cervical dilatation of 4 cm to a dilatation of 6 cm; and allowing women who have previously given birth to push for at least 2 hours, with 3 hours of pushing for women who have not previously given birth, before labor arrest is considered. Physical exercise during pregnancy decreases the risk. Additionally, results from a 2021 systematic review of the evidence on outpatient cervical ripening found that in women with low-risk pregnancies, the risk of caesarean delivery with harm to the mother or child was not significantly different from when done in an inpatient setting.

Risks

Adverse outcomes in low-risk pregnancies occur in 8.6% of vaginal deliveries and 9.2% of caesarean section deliveries.

Mother

In those who are low risk, the risk of death for caesarean sections is 13 per 100,000 vs. for vaginal birth 3.5 per 100,000 in the developed world. The United Kingdom National Health Service gives the risk of death for the mother as three times that of a vaginal birth.
In Canada, the difference in serious morbidity or mortality for the mother was 1.8 additional cases per 100. The difference in in-hospital maternal death was not significant.
A caesarean section is associated with risks of postoperative adhesions, incisional hernias, and wound infections. If a caesarean is performed in an emergency, the risk of the surgery may be increased due to several factors. The patient's stomach may not be empty, increasing the risk of anaesthesia. Other risks include severe blood loss and post-dural-puncture spinal- headaches.
Wound infections occur after caesarean sections at a rate of 3–15%. The presence of chorioamnionitis and obesity predisposes the woman to develop a surgical site infection.
Women who had caesarean sections are more likely to have problems with later pregnancies, and women who want larger families should not seek an elective caesarean unless medical indications to do so exist. The risk of placenta accreta, a potentially life-threatening condition that is more likely to develop where a woman has had a previous caesarean section, is 0.13% after two caesarean sections, but increases to 2.13% after four and then to 6.74% after six or more. Along with this is a similar rise in the risk of emergency hysterectomies at delivery.
Mothers can experience an increased incidence of postnatal depression, and can experience significant psychological trauma and ongoing birth-related post-traumatic stress disorder after obstetric intervention during the birthing process. Factors like pain in the first stage of labor, feelings of powerlessness, intrusive emergency obstetric intervention are important in the subsequent development of psychological issues related to labor and delivery.

Subsequent pregnancies

Women who have had a caesarean for any reason are somewhat less likely to become pregnant again as compared to women who have previously delivered only vaginally.
Women who had just one previous caesarean section are more likely to have problems with their second birth. Delivery after previous caesarean section is by either of two main options:
Both have higher risks than a vaginal birth with no previous caesarean section. A vaginal birth after caesarean section confers a higher risk of uterine rupture, blood transfusion or endometritis, and perinatal death of the child. Furthermore, 20% to 40% of planned VBAC attempts end in caesarean section being needed, with greater risks of complications in an emergency repeat caesarean section than in an elective repeat caesarean section. On the other hand, VBAC confers less maternal morbidity and a decreased risk of complications in future pregnancies than elective repeat caesarean section.

Adhesions

Several steps can be taken during abdominal or pelvic surgery to minimize postoperative complications, such as developing adhesions. Such techniques and principles may include:
  • Handling all tissue with absolute care
  • Using powder-free surgical gloves
  • Controlling bleeding
  • Choosing sutures and implants carefully
  • Keeping tissue moist
  • Preventing infection with antibiotics given intravenously to the mother before skin incision
Despite these proactive measures, adhesion formation is a recognized abdominal or pelvic surgery complication. To prevent adhesions from forming after caesarean section, adhesion barrier can be placed during surgery to minimize the risk of adhesions between the uterus and ovaries, the small bowel, and almost any tissue in the abdomen or pelvis. This is not current UK practice, as there is no compelling evidence to support the benefit of this intervention.
Adhesions can cause long-term problems, such as:
  • Infertility, which may end when adhesions distort the tissues of the ovaries and tubes, impeding the normal passage of the egg from the ovary to the uterus. One in five infertility cases may be adhesion-related
  • Chronic pelvic pain, which may result when adhesions are present in the pelvis. Almost 50% of chronic pelvic pain cases are estimated to be adhesion-related
  • Small bowel obstruction: the disruption of normal bowel flow, which can result when adhesions twist or pull the small bowel.
The risk of adhesion formation is one reason why vaginal delivery is usually considered safer than elective caesarean section where there is no medical indication for section for either maternal or fetal reasons.