Pregnancy outcomes and effects on cardiac function among patients with Tetralogy of Fallot: A single-center cohort study

Data on the characteristics and outcomes of pregnancy amongst patients with Tetralogy of Fallot (TOF) is limited. Depending on the hemodynamic status of the patient, the risk of maternal and fetal complications during pregnancy can be considerable. We aimed to systematically evaluate maternal, obstetric, and fetal outcomes, and assess longitudinal changes in cardiac function among women with TOF using serial imaging. Pregnant adult patients with TOF between 2014 and 2022 were included. We examined maternal and obstetric outcomes during pregnancy. We assessed serial imaging to evaluate the temporal effects of pregnancy on cardiac function. Our cohort included 50 patients. There were 85 pregnancies overall with 79 live births (92.9 %). The median gestational age at delivery was 38.3 [37.0–39.1] gestational weeks (GW), nine deliveries (11.3 %) occurred before 37 GW, but only one before 34 GW. The median birthweight at delivery was 2850 [2450–3048] grams. The main fetal complication was small for gestational age (n = 16,22 %). There were no deaths in the peripartum period or the year following pregnancy. There were no significant valvular or ventricular functional differences when comparing pre-conception to post-conception echocardiogram data. In the subgroup with availability of MRI data, the Right ventricular end-diastolic volume index increased significantly post-pregnancy (109 ± 37.9 ml/m 2 vs 117 ± 25.0 ml/m 2 , p < 0.01). Maternal and obstetric complications are rare among patients with TOF. Our initial findings suggest that pregnancy does influence cardiac dimensions on serial long-term imaging follow-up but further, expanded long-term data is needed. • Data on pregnancy outcomes in women with Tetralogy of Fallot (TOF) remain limited. • Maternal and obstetric complications are rare among women with TOF. • Pregnancy increases right ventricular volumes, but pulmonary valve function stays stable. • Pregnancy affects cardiac size but does not accelerate pulmonary valve deterioration.