A repeat C-section is any Cesarean delivery following a previous Cesarean birth. This surgical route is common, often representing a deliberate choice made after considering risks and benefits. When a woman has a history of prior Cesarean delivery, the decision for the next birth involves navigating between a planned repeat procedure and attempting a vaginal delivery. The choice is highly individualized, depending on specific medical history and patient preferences.
Defining Repeat Cesarean Delivery
The initial surgical delivery is termed a primary C-section, while all subsequent Cesarean births are classified as repeat Cesarean deliveries. Medical professionals use specific terminology to distinguish the circumstances of the surgery. An Elective Repeat Cesarean Delivery (ERCD) is a procedure scheduled in advance, usually performed before the onset of labor.
This planned approach contrasts with a repeat C-section that happens after a Trial of Labor After Cesarean (TOLAC) has failed, or one required due to an emergency during labor. The factors leading to a repeat C-section can be categorized as recurrent or non-recurrent. Recurrent reasons include a physical condition, such as a contracted pelvis, or a patient’s choice to avoid the risks associated with labor after a uterine scar.
In many cases, the original reason for the primary C-section, such as failure to progress, may recur in the subsequent pregnancy. However, a significant portion of repeat procedures are performed solely because of the prior uterine surgery, often based on the patient’s desire or a provider’s recommendation to mitigate the chance of uterine rupture during labor.
The Primary Alternative: Trial of Labor After Cesarean
For many women, the primary alternative to a repeat Cesarean is a Trial of Labor After Cesarean (TOLAC), aiming for a Vaginal Birth After Cesarean (VBAC). This option is offered to women who have had one previous Cesarean delivery with a low transverse uterine incision. This low-horizontal cut is significantly less likely to rupture during labor than a classical, or vertical, incision.
Success rates for VBAC are favorable, with approximately 60% to 80% of women who attempt TOLAC achieving a vaginal delivery. Factors that increase success include having a prior vaginal delivery and the spontaneous onset of labor. Conversely, advanced maternal age, a short interval between pregnancies, or the need for labor induction can decrease the chances of a successful outcome.
TOLAC is not considered safe for all women, and absolute contraindications exist. These include a history of a previous uterine rupture, or a classical or “T”-shaped uterine incision. Due to the small but serious risk of uterine rupture (estimated between 0.47% and 0.9% for women with one prior low transverse scar), continuous fetal heart rate monitoring is necessary during active labor. TOLAC should only occur in facilities equipped with staff and resources immediately available to perform an emergency Cesarean delivery, including surgical and anesthesia teams. This ensures complications can be addressed quickly to ensure maternal and fetal safety.
Planning and Scheduling the Repeat Procedure
If the decision is made to proceed with a repeat Cesarean delivery, the procedure is typically scheduled at 39 weeks of gestation. This timing maximizes fetal maturity while minimizing the risk that the mother will spontaneously go into labor. Delivering too early risks respiratory complications for the newborn, while waiting too long increases the chance of an unplanned emergency Cesarean.
Pre-operative planning includes routine blood work, such as a complete blood count and blood typing for potential transfusion, usually performed within 72 hours of the surgery. Patients also consult with an anesthesiologist to review their medical history, discuss anesthesia options like a spinal block, and formulate a postoperative pain management plan.
Specific instructions are given regarding fasting to prevent aspiration of stomach contents under anesthesia. Patients stop eating solid foods eight hours before the procedure but may drink clear liquids up to two hours prior. Antiseptic washes, such as chlorhexidine, are often provided for the patient to use at home before coming to the hospital, aiming to reduce the risk of surgical site infection.
Unique Risks Associated with Subsequent Cesarean Deliveries
The presence of a prior uterine incision introduces specific surgical challenges and risks unique to repeat Cesarean deliveries. One common issue is the formation of scar tissue, known as adhesions, which can make subsequent surgery more difficult. Adhesions are bands of fibrous tissue that can cause organs like the bowel and bladder to stick to the previous surgical site.
Dissection of these adhesions during the repeat procedure increases operative time and raises the risk of accidental injury to surrounding structures, such as the bladder or intestines. The risk and density of these adhesions tend to increase with the number of previous Cesarean sections a woman has undergone. This heightened complexity requires the surgeon to proceed with meticulous care to safely reach the uterus.
A more serious concern is the increased likelihood of abnormal placental implantation, collectively known as the Placenta Accreta Spectrum (PAS). This occurs when the placenta attaches too deeply into the uterine wall, sometimes invading the muscle or penetrating through the uterus. The risk of PAS rises sharply with the number of prior Cesarean deliveries, especially if the placenta is lying low (Placenta Previa). For example, the risk of PAS with Placenta Previa and one prior Cesarean is significantly lower than the risk with three or more prior Cesarean sections. This condition often leads to massive hemorrhage at delivery and may require a hysterectomy to control bleeding.