Analysis of Ultrasound Findings and Outcomes in Fetuses with Suspected Congenital Heart Disease at Less than 14 Weeks' Gestation Compared to Later Gestations.

Introduction: This study aimed to compare the spectrum of cardiac anomalies, associated comorbidities, and outcomes in fetuses suspected of congenital heart disease (CHD) at less than 14 weeks' gestation with those in the later gestations.

Methods: We conducted a 3-year retrospective study involving 352 fetuses suspected of CHD at our institution. The fetuses were divided into two groups based on the gestational age at which the CHD was initially detected. Initial CHD suspicion was noted within 14 weeks, forming group I. The remaining fetuses, initially suspected of CHD after 14 weeks, constituted group II. The type of CHD, ultrasound soft markers (USMs), associated extracardiac structural abnormalities (ECSAs), genetic testing results, and pregnancy outcomes were retrieved.

Results: The types of CHD in group I (n = 76) were less varied than those in group II (n = 276). Isolated CHD was significantly more prevalent in group II (odds ratio [OR] = 0.170, 95% confidence interval [CI]: 0.092-0.316, p < 0.001). The frequency of ECSA and USMs was significantly greater in Group I (OR = 1.816, 95% CI: 1.180-2.795, p < 0.01; OR = 4.400, 95% CI: 3.375-5.737, p < 0.001, respectively). Chromosomal abnormalities were more prevalent in group I than in group II (65.0% vs. 16.5%, p < 0.001). There were no significant differences in termination rates between the two groups (OR = 1.099, 95% CI: 1.023-1.179, p = 0.043).

Conclusion: The spectrum of diagnosed cardiac abnormalities differs between early and mid stages. Non-isolated cardiac abnormalities and chromosomal anomalies are more readily detectable in the early stages of pregnancy before the formal establishment of early cardiac screening programs. Early suspicion of cardiac anomalies may not be the predominant factor driving the termination decision.