The Heart of Fetal Growth Restriction: Congenital Heart Defects—An Analysis of Risk Factors and Morbidity Outcomes

Background: Congenital heart disease (CHD) co-occurring with fetal growth restriction (FGR) is clinically important but incompletely characterized. We assessed the proportion and subtype spectrum of CHD in term-born children with FGR, and factors associated with its presence and complexity. Methods: Retrospective analysis of 375 term singleton children with documented FGR at a tertiary pediatric center. CHD required echocardiographic confirmation; isolated patent foramen ovale was excluded. Patients with multiple lesions were hierarchically classified as simple or complex. Multivariable logistic regression was restricted to characteristics available at or before birth. Results: CHD was confirmed in 96/375 children (25.6%): 71 (74.0%) simple, 25 (26.0%) complex. Atrial septal defect and patent ductus arteriosus were most frequent (each 45.8%), followed by patent foramen ovale (44.8%) and ventricular septal defect (32.3%). Severe FGR (aOR 2.012, 95% CI 1.222–3.313; p = 0.006) and genetic syndrome (aOR 5.969, 95% CI 2.565–13.889; p < 0.001) were independently associated with CHD presence. Within the CHD subgroup, genetic syndrome was also associated with complex disease (aOR 5.156, 95% CI 1.651–16.104; p = 0.005). Diagnosis occurred before six months in 95.8%. Hospitalization outcomes and comorbidity burden did not differ by complexity. Conclusions: FGR severity and genetic syndrome were both independently associated with the presence of a cardiac defect, and genetic syndrome was further associated with its complexity. These findings support targeted rather than universal echocardiographic assessment. Directionality cannot be established from postnatal data.