What are the potential intra‑operative and postoperative complications of a lower segment cesarean section?

Potential Complications of Lower Segment Cesarean Section

Lower segment cesarean section carries significant risks of both intraoperative and postoperative complications, with the most critical being hemorrhage, infection, and injury to adjacent structures, particularly when performed emergently during labor.

Intraoperative Complications

Hemorrhage and Blood Loss

• Excessive blood loss (≥1000 mL) occurs in approximately 7.3% of cesarean deliveries 1
• Risk increases dramatically with emergency procedures, particularly during second-stage labor 2, 3
• Uterine atony is the most common cause of postpartum hemorrhage, occurring in >75% of hemorrhagic cases 4

Uterine Injury

• Unintentional hysterotomy extensions are among the most common complications, particularly with second-stage cesarean deliveries 3
• Uterine corpus lacerations occur in approximately 10.1% of cases 1
• Extensions are reliably associated with greater blood loss, higher transfusion rates, and longer operative times 3
• Uterine artery injury occurs 4 times more frequently in emergency (red code) cesareans compared to non-urgent procedures (7.1% vs 1.7%) 2

Adjacent Organ Injury

• Urinary tract injuries can occur during bladder dissection, especially with adhesions from prior cesarean deliveries 5, 6
• Risk increases with repeat cesarean sections due to altered anatomy and adhesions 6

Surgical Technique-Related Complications

Blunt expansion of the transverse uterine hysterotomy is recommended to reduce surgical blood loss 7. The evidence shows that two-layer hysterotomy closure may reduce future uterine rupture risk 7.

Postoperative Complications

Infectious Complications

The overall postoperative morbidity rate is approximately 35.7%, with infectious complications being predominant 1:

• Fever: 24.6% of cases 1
• Endometritis and wound infections: Significantly reduced with proper prophylaxis 7
• Urinary tract infections: 3.0% of cases 1
• Clostridioides difficile infection: Increased risk with clindamycin use in penicillin-allergic patients 8

Prophylactic antibiotics must be administered within 60 minutes before skin incision 7. First-generation cephalosporins are recommended for all women, with azithromycin added for those in labor or with ruptured membranes 7.

Wound Complications

• Hematoma formation: 3.5% of cases 1
• Wound separation: Reduced with subcuticular suture closure compared to staples 7
• Reapproximation of subcutaneous tissue ≥2 cm thick reduces wound complications 7

Thromboembolic Complications

• Venous thromboembolism (VTE) incidence: 2.6 per 1,000 cesarean deliveries 9
• Risk is 2-fold higher than vaginal delivery 7
• Mechanical prophylaxis (compression stockings, pneumatic compression devices) should be used until full ambulation 9
• Pharmacologic prophylaxis increases wound separation and hematoma risk 9

Emergency-Specific Risks

Emergency cesarean sections carry substantially higher complication rates 2, 1:

• Major intraoperative complications: 16.9% in red code (immediate) vs 9.9% in non-urgent cases 2
• Major postoperative complications: 12.4% in red code vs 1.7% in non-urgent (OR 8.5) 2
• Secondary cesarean (after failed vaginal delivery) has the highest complication rate at 23.4% 1

Chronic/Long-term Complications

Adhesion-Related

• Intra-abdominal adhesions: 24-46% after first cesarean, up to 59% after repeat cesareans 10
• Bowel obstruction: 2.92 times higher risk compared to vaginal delivery 11
• Surgery for bowel obstruction: 2.12 times higher risk 11
• Small bowel herniation through the cesarean wound is rare but can present deceptively as cellulitis 12

Abdominal Wall Complications

• Incisional hernia: 2.71 times higher risk; surgery for hernia 3.35 times higher risk 11
• Chronic scar pain: Reported by 10% of women at 12 months post-cesarean 10
• Abdominal wall endometriosis can develop at the incision site 5

Future Pregnancy Complications

• Placenta previa incidence increases progressively: 9/1,000 after one cesarean, 17/1,000 after two, 30/1,000 after three or more 13
• Placenta accreta spectrum disorders: Risk increases 0.25-3% with each subsequent cesarean 7
• Uterine rupture risk in subsequent labor: Varies by induction method if attempting VBAC 13:
  • Oxytocin: 1.1%
  • Prostaglandin E2: 2%
  • Misoprostol: 13%
• Cesarean scar defects and cesarean scar ectopic pregnancy are recognized chronic complications 5
• Spontaneous preterm birth in subsequent pregnancies may be increased with cervical or lower-segment trauma 3

Cumulative Risk with Multiple Cesareans

After the second repeat cesarean, risks escalate 7:

• Wound/uterine hematoma: 4-6%
• Red cell transfusions: 1-4%
• Hysterectomy: 0.5-4%
• Placenta accreta: 0.25-3%

Risk Modifiers

Smoking, obesity, and multiple prior cesarean deliveries significantly amplify complication risks 11. Emergency procedures, particularly during active labor or second stage, carry the highest immediate complication burden 2, 1, 3.

Prevention Strategies

Key evidence-based preventive measures include 7:

• Chlorhexidine-alcohol for abdominal skin preparation (preferred over povidone-iodine)
• Vaginal preparation with povidone-iodine solution
• Regional anesthesia preferred over general anesthesia
• Prevention of intraoperative hypothermia with forced air warming and warmed IV fluids
• Maintenance of euvolemia throughout the perioperative period
• Subcuticular suture for skin closure