Abstract
Introduction: Pregnancy in women with unrepaired single-ventricle physiology is rare and associated with substantial maternal and foetal risk. Evidence regarding pregnancy outcomes in this population remains limited. Case description: We report three successful pregnancies in two women with unrepaired double-inlet left ventricle, transposition of the great arteries and valvular/sub-valvular pulmonary stenosis. Both women were classified as modified World Health Organization class IV and received multidisciplinary care throughout pregnancy. Despite complex congenital heart disease, systemic ventricular function and oxygen saturation remained stable. All three pregnancies resulted in live births. However, foetal growth restriction, oligohydramnios, placental insufficiency, prematurity and prolonged neonatal hospitalisation occurred in all pregnancies. One patient successfully completed two consecutive pregnancies without maternal cardiovascular deterioration. Discussion: Pulmonary outflow obstruction, relatively preserved oxygen saturation and stable systemic ventricular function may have contributed to maternal haemodynamic stability. However, substantial foetal and neonatal morbidity in all three pregnancies underscores that favourable maternal outcomes do not establish pregnancy safety in this population. Conclusion: Carefully selected women with unrepaired single-ventricle physiology and balanced circulation may tolerate pregnancy better than expected, although foetal complications remain common. Multidisciplinary management in specialised congenital heart disease centres is essential.