Transcending the Natural History: A Rare Case of Successful Pregnancy in a Woman with Unrepaired Truncus Arteriosus Type I

BackgroundPregnancy in women with uncorrected truncus arteriosus Type I complicated by Eisenmenger physiology is associated with extremely high maternal mortality and is generally contraindicated.Survival into reproductive age without surgical correction is uncommon, and only a handful of pregnancies in women with unrepaired truncus arteriosus have been reported in the literature. Case PresentationWe report a case of successful delivery in a 27-year-old primigravida with uncorrected truncus arteriosus complicated by severe pulmonary arterial hypertension and Eisenmenger physiology.Despite counselling in early pregnancy regarding the extremely high maternal risk, the patient opted to continue the pregnancy.She presented at 34 weeks of gestation with severe preeclampsia and profound hypoxemia, with oxygen saturation as low as 59% on room air.Following stabilization with multidisciplinary care, elective preterm cesarean section was performed under epidural anesthesia.Postoperatively, the patient required intensive care management with non-invasive ventilation and oxygen support.She was discharged in stable condition on postoperative day 8 with advice regarding long-term home oxygen therapy and close cardiology follow-up.Conclusion This case highlights the importance of coordinated multidisciplinary management in an exceptionally high-risk pregnancy complicated by uncorrected truncus arteriosus and Eisenmenger physiology.Favorable maternal and neonatal outcomes, though rare, may be achievable with meticulous perioperative care, intensive monitoring, and timely intervention.