Risk factors and diagnostic challenges in a nullipara with spontaneous uterine rupture during vaginal delivery

OBJECTIVE: To present a rare case of uterine rupture after vaginal delivery under epidural anesthesia in a nulliparous woman without prior uterine surgery. CASE REPORT: A 38-year-old primiparous woman with a history of infertility conceived through in vitro fertilization. At 39 weeks of gestation, she was admitted due to spontaneous premature rupture of membranes. Oxytocin was administered for labor augmentation, and fundal pressure was applied for maternal exhaustion, leading to the delivery of a healthy infant. Secondary laceration of perineum was found but no cervical laceration was detected just after vaginal delivery. Primary repair was performed layers by layers smoothly. Shortly after delivery, the patient developed hypotension, tachycardia, nausea, and poor uterine tone, but without abdominal pain, likely due to epidural anesthesia masking symptoms. Abdominal ultrasound revealed intrauterine clots and some fluid in the cul-de-sac, suggesting uterine rupture. An emergent laparotomy identified a 10 cm posterior uterine laceration, which was successfully repaired. CONCLUSION: This case highlights the importance of promptly recognizing atypical or subtle signs of uterine rupture particularly when classical symptoms are masked by epidural anesthesia. Clinicians should maintain a highly suspicion and closely monitor for alternative indicators, such as hemodynamic instability or abnormal fetal heart rate patterns. In addition, fundal pressure should be applied with caution, especially in patients with risk factors for uterine rupture such as myomectomy, to minimize the risk of adverse maternal outcomes.