Risk Assessment and Management of Impending C-Scar Rupture at 20 Weeks Pregnancy

Immediate Risk Assessment

• At 20 weeks gestation, the fundus reaches approximately the umbilicus, making aortocaval compression physiologically relevant, as noted by the American Heart Association 1, 2

Quantified Rupture Risk

• The overall uterine rupture prevalence in women with prior cesarean section is 22 per 10,000 births (0.22%), but this increases dramatically to 35 per 10,000 (0.35%) when labor occurs, according to the World Health Organization 3, 4
• Risk factors that increase rupture probability include inter-delivery interval <18 months, classic uterine scar, and multiple prior cesarean sections, as reported by the American Academy of Family Physicians 5, 6

Management Algorithm at 20 Weeks

Critical Diagnostic Features

• Ultrasound assessment of scar: Cesarean scar defects (niches) are present in 24-88% of women with prior cesarean section, as noted by the World Health Organization 3, 4
• Document number of prior cesarean sections: Risk increases with each additional cesarean (placenta accreta risk: 12.9/10,000 after one CS, 41.3/10,000 after two CS, 78.3/10,000 after three CS), according to the World Health Organization 3, 4

Positioning and Monitoring After 20 Weeks

• Left uterine displacement should be maintained during any procedures to prevent aortocaval compression, as recommended by the European Society for Medical Oncology 7, 8
• Ensure adequate maternal oxygenation and optimal uteroplacental perfusion during any surgical intervention, as suggested by the European Society for Medical Oncology 7, 8