Rebecca B. Singson, MD, FPOGS, FACS, FPSGE, FPSCPC

A Cesarean section or C section is a surgical delivery of one baby or multiple babies by cutting through the mother’s abdomen and the uterine wall. If the surgery is scheduled ahead of time, it is referred to as an elective cesarean section (as opposed to an unscheduled emergency Cesarean section). There has been an increased rate of Cesarean sections recently According to Williams Obstetrics, these are the following indications for C sections:

MATERNAL INDICATIONS

Prior Cesarean delivery – because of the scar in the uterus, there is a risk of uterine rupture if the mother goes into labor after a previous Cesarean delivery although it is said to be <1%.

Abnormal placentation – this may be due to placenta previa or placenta accreta. Placenta previarefers to low implantation of the placenta. It classically presents as painless vaginal bleeding in the third trimester secondary to an abnormal placentation near or covering the internal cervical os.

Placenta accreta is when the placentagrows too deeply into the uterine wall.It can cause massive bleeding usually after delivery, since the placenta fails to detach.

Maternal request – a mother may elect to deliver by C section before or after going into labor even when there is no firm indication for a C section. Women who desire elective primary Cesarean delivery should be presented with the advantages and disadvatages. Although a C section may offer decreased risks for hemorrhage and chorioamnionitis compared with a planned primary vaginal birth, it does carry with it the disadvantage of higher rates of maternal thromboembolism, hysterectomy, and re-hospitalization for infection or wound complications; longer initial hospital stays; and higher chances of uterine rupture or abnormal placental implantation in subsequent pregnancies.3,4,5 Women who undergo a Cesarean delivery are much more likely to be delivered by a repeat operation in subsequent pregnancies.

Another advantage of a Cesarean delivery is that it is associated with lower rates of urinary incontinence and pelvic organ or uterine prolapse.6,7,8,9,10

Prior classical hysterotomy the uterus – if there has been a previous Cesarean section where the uterus has been incised the Classical way, which means the uterus was incised in the contractile portion of the uterus, there is an indication to perform a subsequent Cesarean section. Because the risk of uterine rupture in women with prior Classical Cesarean deliveryis about 9%11 it may be prudent to schedule a repeat Cesarean deliveryat 36-37 weeks. The danger, though, is the higher risk for respiratory distress syndrome in the fetus.

Unknown uterine scar type – if a patient has undergone a previous surgery on the uterus whether for a removal of a myoma or a previous C section, or if it is unknown whether a low cervical Cesarean section or a Classical Cesarean section was performed, there is an indication to perform a repeat Cesarean section.

Uterine incision dehiscence – Cesarean section in advanced labor is associated with increased risk of incomplete healing of the uterine incision leading to uterine incision dehiscence. The reported incidence of this condition ranges between 0.2% and 4.3% of all pregnancies associated with a previous C section.12 A repeat C section is indicated to repair the thinned out uterine wall.

Prior full-thickness myomectomy – A myomectomy scars the uterus and increases the risk for uterine rupture with subsequent pregnancy if allowed to go into labor.

Genital tract obstructive mass – the presence of a myoma in the cervix, or a vaginal tumor would be some types of genital obstructive masses that would prevent a normal birth and would have to be delivered by C section.13

Invasive cervical cancer – Women with cervical cancer are better delivered by C section than by vaginal birth.The recommendation is based on the finding that women diagnosed with cervical cancer within 6 months after delivering a baby, particularly vaginally, had poorer survival and higher risk of recurrent disease than women who were diagnosed with cervical cancer during their pregnancy.

Prior trachelectomy – Patients who underwent removal of the cervix for benign or malignant reasons are better delivered by Cesarean section.

Permanent cerclage – patients with incompetent cervix with permanent cercalge to keep the cervix closed may undergo an elective C section.

Prior pelvic reconstructive surgery – there are some women, especially those with exposure to a drug called diethylstilbestrol, who develop abnormalities in their reproductive organs like a double uterus, or a uterus with a septum, etc. These can cause infertility and therefore, may need reconstruction to unify the uterus or remove the septum. In some procedures which involve cutting through the uterus to unify the two cavities, called the Strassman procedure, it will be necessary to deliver by Cesarean section to prevent the uterus from rupturing on or before labor.

Pelvic deformity – there are certain types of pelvic bones that cannot support a vaginal birth. In the past, this was validated by x-rays, called x-ray pelvimetry. But present practice guidelines no longer favor exposing the fetus to radiation but instead favoring a trial of labor and an eventual C section should labor not progress. The reason for this is that even if the x ray pelvimetry reports a contracted pelvis, but the fetus is small, the baby can still be successfully be delivered vaginally.

Herpes Simplex Virus infection – if active lesions are present at the onset of labor, a Cesarean section should be recommended to prevent the fetus from acquiring the virus.14 However, if the membranes have been ruptured for more than 6 hours, it is not certain that a Cesarean section would benefit the baby. A Cesarean section can reduce, but cannot totally eliminate, the risk of newborn infection.14,15. A recent study found that a Cesarean section delivery reduces the risk of HSV among newborns by 86%16.

Human Papilloma Virus infection – HPV DNA has been detected in amniotic fluid, placenta, and the umbilical cord.17 Both chorionic and placental tissue can be infected through the hematogenous (by blood) route and hence, HPV can be spread to amniotic cells that are then ingested by the fetus18,19. Another possible route of transmitting the HPV virus is through the placenta. The virus can possibly go up via the maternal genital tract, since it has been shown that the HPV-DNA can be present, both in amniotic fluid19 and the umbilical cord,18 in pregnant women with cervical intraepithelial lesions.

Cardiac disease – various researches bear out that women with heart disease end up with a Cesarean section more often then healthy women. 20,21 However, the fact is, in patients with cardiac problems, the preferred mode of delivery is via a vaginal birth, since a Cesarean section is associated with more blood loss and higher thromboembolic and infection risk. A Cesarean section in a woman with heart disease is reserved only for obstetric indications. Examples of situations in which primary a Cesarean section should be considered are: if a woman goes into labor while on oral anticoagulants (because of risk of fetal intracranial bleeding), Marfan syndrome with diameter of the ascending aorta >45mm, acute or chronic dissection, and acute heart failure.22

Pathology requiring concurrent intra-abdominal surgery – if a woman develops cervical or ovarian cancer that requires a hysterectomy after delivery of the baby, it is warranted to perform a CS hysterectomy.

Perimortem Cesarean delivery – In cases where the mother is dying or dies while pregnant from an accident, heart diseases or cancer, etc, the baby has to be evacuated as a life-saving measure.

MATERNAL-FETAL INDICATIONS

Cephalopelvic disproportion (CCPD)– it is a condition when a baby’s head or body is too big to fit through the mother’s pelvis. Many cases of “failure to progress” during labor are given a diagnosis of CPD. Risk factors for CPD are Estimated Fetal weight of > 3,000 g, pre-pregnancy body mass index (BMI) > or = 25 kg/m2, nulliparity (never been pregnant before) and the inadequacy of clinical pelvimetry.23

Failed operative vaginal delivery – In the past, the forceps and vacuum were used to deliver the head for the more difficult cases of cephalopelvic disproportion. As cesarean delivery became more widely available in the early to mid-20thcentury, new practices were developed to minimize morbidity and maximize safety of operative vaginal delivery.One such practice which evolved, is the concept of a trial of forceps or vacuum. This approach utilizes a double set- up such that if the forceps or vacuum fails, an immediate cesarean delivery can be done.24

Placenta previa or placental abruption – a low-lying placenta, especially if it covers part or all of the internal opening of the cervix necessitates delivery by Cesarean section. Abruptio placenta involves partial or total premature separation of the placenta while the fetus is still in the womb, thus, cutting the oxygen supply to the fetus. It is a dire, life-threatening emergency which may need immediate C section.

FETAL INDICATIONS

Non-reassuring fetal status – Late decelerations (drop in fetal heart rate below 120 beats/min), bradycardia (slowed heart rate) less than 70 beats per minute, and abnormal fetal heart rate patterns during the first stage of labor might jeopardize fetal well-being, and an expedited delivery should be considered.25

If a vaginal birth is not imminent and the forceps or vacuum cannot be used, an emergency Cesarean section should be performed.

Malpresentation – if the baby’s head is not presenting properly in the birth canal, this may result in failure of the labor to progress. This can happen when the baby is in breech (the buttocks are in the birth canal instead of the head), face, brow, and compound presentations as well as when the baby is in a transverse lie. Risk factors include multiple pregnancies, previously affected pregnancy, polyhydramnios (too much amniotic fluid, i.e., amniotic fluid index above 18), and fetal and uterine anomalies.26

Macrosomia – The term fetal macrosomia implies fetal growth beyond a specific weight, usually 4,000 g (8 lb, 13 oz) or 4,500 g (9 lb, 4 oz), regardless of the fetal gestational age.In macrosomic infants, the risk of fracture of the clavicular bone in the shoulder and brachial plexus injury is approximately 10-fold and 18- to 21-fold, respectively, when birth weight is more than 4,500 g. The risk of Cesarean delivery in women attempting a vaginal delivery at least doubles when the fetal weight is estimated to be more than 4,500 g.27

Congenital anomaly – Cesarean delivery may improve neonatal outcome for fetuses with isolated brain deformities like meningomyelocele, hydrocephalus with concomitant macrocephaly, anterior wall defects with extracorporeal liver, sacrococcygeal teratomas, hydrops, and alloimmune thrombocytopenia with low platelet count at term. Hydrocephalus without macrocephaly, anterior wall defects without an extracorporeal liver, ovarian cysts, skeletal dysplasias, fetuses whose mothers have immune thrombocytopenic purpura and fetuses with alloimmune thrombocytopenia with acceptable platelet counts may safely be delivered vaginally.28

Abnormal umbilical cord Doppler study – Fetal Doppler flow velocimetry of umbilical and middle cerebral arteries allow for finding of the most proper time of high-risk pregnancy termination, hence should be considered in the elective cesarean sections.29

Thrombocytopenia – this is a condition with low platelet count in the blood and therefore makes the mother more prone to bleeding. Thrombocytopenia is second only to anemia as the most common hematologic abnormality during pregnancy.30

Prior neonatal birth trauma – “Traumatic birth” may refer to physical injury, as well as psychological trauma. In a traumatic birth, it is found that women lose more than just their dream of birth and usually judge themselves to be inadequate in some way. A traumatic birth may arise from the mother’s perceptions in relation to the use of pitocin, forceps, vacuum extraction, and Cesarean section. It can also be related to fear of maternal or fetal death, unrelieved pain during labor and/or childbirth, long and difficult labor, perceived loss of control during the childbirth experience, and a dead or damaged infant.31

Obstetricians must recognize the potential benefits as well as risks of an elective Cesarean section among the birth options for a select group of previously traumatized pregnant women. Although, with support, many women successfully deal with their prior birth trauma, some women, even with therapy, cannot come to terms with it. Therefore it is reasonable to seriously consider their request for an elective Cesarean birth in order to prevent further trauma.32

Risks to the baby during Cesarean section include:

• Breathing problems. Several studies have documented the high incidence of respiratory distress and NICU admissions in infants born by Cesarean delivery before the onset of spontaneous labor.33,34 Babies born by scheduled C section are more likely to develop transient tachypnea — a breathing problem marked by abnormally fast breathing during the first few days after birth.
• Surgical injury.Although rare, accidental nicks to the baby’s skin on the baby’s head, face or whatever part is next to the uterus as the obstetrician is incising the uterus.

Risks to the mother during Cesarean section include:

• Infection.After a C section, the mother might be at risk of developing an infection of the lining of the uterus (endometritis). This can be caused by vaginalbacteria entering the uterus during childbirth and causinginfection within six weeks of the birth (postpartum endometritis). Postpartum endometritis occurs after about 1% to 3% of vaginal births, and up to 27% of cesarean births. Prolonged rupture of the membranes (breaking the bag of water that surrounds the baby) and multiple vaginal examinations during birth also appear to increase the risk.35
• Postpartum hemorrhage (PPH). A C section might cause heavy bleeding during and after delivery. The PPH rate in an emergency Cesarean (6.75%) was greater than after an elective Cesarean (4.84%). Risk factors for PPH after an elective operation include the presence of fibroids or leiomyomata, blood disorders, placenta previa, antepartum bleeding, preterm birth, and general anesthesia. Emergecy Cesarean PPH risk factors included blood disorders, retained placenta, antepartum transfusion, antepartum/intrapartum hemorrhage, placenta previa, general anesthesia, and macrosomia.36
• Reactions to anesthesia.Adverse reactions to any type of anesthesia are possible. Luckily, in spite of an increase in the number of Cesarean sections, the incidence of anesthetic-related complications remains low. This is due primarily to the increasing use of regional anesthesia (spinal and or epidural anesthesia). With spinal anesthesia, spinal headaches may occur, and rarely, infection on the site. General anesthesia, on the other hand, a is associated with a 17-fold increase in complications, in particular, failed endotracheal intubation, aspiration of gastric contents and hypoxia.37
• Blood clots.A C section might increase the risk of developing a blood clot inside a deep vein, especially in the legs or pelvic organs (deep vein thrombosis). If a blood clot travels to the lungs and blocks blood flow (pulmonary embolism), the damage can be life-threatening.
• Wound infection.Depending on the risk factors and whether an emergency C section is needed, one might be at increased risk of an incision infection.
• Surgical injury.Although rare, surgical injuries to the bladder or bowel can occur during a C section. If there is a surgical injury during the C-section, additional surgery might be needed.
• Increased risks during future pregnancies.After a C section, one is faced with a higher risk of potentially serious complications in a subsequent pregnancy than after a vaginal delivery. The more C sections a woman has, the higher the risks of placenta previa and a condition in which the placenta becomes abnormally attached to the wall of the uterus (placenta accreta). The risk of the uterus tearing open along the scar line from a prior C section (uterine rupture) is also higher if a VBAC is attempted.

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