Association Between Fetal Congenital Heart Disease and Assisted Reproductive Technologies in the First Trimester of Pregnancy: A Retrospective Study

OBJECTIVE: To determine whether there is a higher rate of major fetal congenital heart diseases (CHDs) at first-trimester scan in pregnancies conceived by assisted reproductive technology (ART). METHODS: A retrospective study was conducted from 2014 to 2022. It included 20,009 singleton pregnancies undergoing ultrasound between 11 and 15 weeks for first-trimester aneuploidy screening or referral for suspected fetal abnormality. Fetal heart assessment was performed through sequential analysis. In cases of CHDs, extracardiac malformations, or other risk factors for major aneuploidies, fetal karyotype evaluation was conducted. CHDs were categorized as major or minor. RESULTS: A CHD was diagnosed in 133 (0.7%) of 18,532 natural pregnancies and 14 (0.9%) of 1477 ART pregnancies. The prevalence of major CHDs in natural pregnancies was 0.5%, with no significant difference compared to ART pregnancies (0.7%; p = 0.47). Overall, 48 CHD cases (43.2%) were associated with extracardiac abnormalities, with no differences between natural and ART pregnancies (p = 0.38). The frequency of abnormal karyotype and isolated CHDs (normal karyotype and no extracardiac abnormalities) also did not differ. CONCLUSION: The rate of major CHDs detectable at the end of the first trimester does not differ between ART and natural pregnancies.