Utility of Screening Fetal Echocardiogram Following Normal Anatomy Ultrasound for In Vitro Fertilization Pregnancies

Abstract

In vitro fertilization (IVF) is associated with a higher incidence of congenital heart disease, resulting in universal screening fetal echocardiograms (F-echo) even when cardiac structures on obstetric scan (OB-scan) are normal. Recent studies suggest that when OB-scan is normal, F-echo may add little benefit and increases cost and anxiety. We aim to determine the utility of screening F-echo in IVF pregnancies with normal cardiac anatomy on prior OB-scan. We conducted a retrospective chart review of IVF pregnancies referred for F-echo at the Seattle Children's Hospital between 2014 and 2020. OB-scan results and subspecialty of interpreting physician (Obstetrics = OB; Maternal Fetal Medicine = MFM; Radiology = Rads), F-echoes, and postnatal outcomes were reviewed. Cardiac anatomy on OB-scans was classified as complete if 4-chamber and outflow-tract views were obtained. Supplemental views (three-vessel and sagittal aortic arch views) on OB-scan were also documented. Of 525 IVF referrals, OB-scan reports were available for review in 411. Normal anatomy was demonstrated in 304 (74%) interpreted by OB (128; 42%), MFM (80; 26%), and Rads (96; 32%). F-echo was normal in 278 (91%). Of the 26 abnormal F-echo, none required intervention (17 muscular and 5 perimembranous ventricular septal defects, and 4 minor valve abnormalities). There was no difference in OB-scan accuracy for identifying normal cardiac anatomy when comparing 4-chamber and outflow-tract views vs. addition of supplemental views (91% vs 92% normal F-echo; p > 0.1). Evaluation of OB-scan accuracy by interpreting physician subspecialty demonstrated normal F-echo in 95%, 85%, and 92% (p = 0.95) as read by OB, MFM, and Rads, respectively. A majority of IVF referrals with normal cardiac anatomy visualized on OB-scan using 4-chamber and outflow-tract views resulted in normal F-echo, regardless of interpreting physician subspecialty or addition of supplemental views. Of the minority with abnormal F-echo, none required intervention. Consideration should be given to the cost/benefit of screening F-echo for the indication of IVF if normal cardiac anatomy is demonstrated on OB-scan.