Fetal cardiac remodeling in twin pregnancy conceived by assisted reproductive technology

Background Recent data suggest that singleton fetuses conceived by assisted reproductive technologies (ART) present cardiovascular remodeling that may persist postnatally. Twin pregnancies are more frequent in the ART population, and are associated with increased adverse perinatal outcomes like hypertensive disorders, gestational diabetes and preterm birth. However, it is unknown whether cardiac remodeling is also present in twin pregnancies conceived by ART. Our aim was to assess the presence of fetal cardiac remodeling and dysfunction in twin pregnancies conceived by ART, as compared to spontaneously conceived (SC) ones. Material and Methods A prospective cohort study including 50 dichorionic twin fetuses conceived by ART and 50 SC twins. The study protocol included structural and functional fetal echocardiography at 28–30 weeks of gestation. Results ART twin fetuses showed significant cardiac changes, predominantly affecting the right heart, such as dilated atria (right atrial/heart area: controls mean 15.7 (SD 3.1) vs ART 18.4 (3.2), p < 0.001), more globular ventricles (right ventricular sphericity index: SC 1.57 (0.25) vs ART 1.41 (0.23), p = 0.001) and thicker myocardial walls (septal wall thickness: SC 2.57 mm (0.45) vs ART 2.84 mm (0.41), p = 0.034) together with reduced longitudinal motion (tricuspid annular plane systolic excursion: SC 6.36 mm ( 0.89) vs ART 5.18 mm (0.93), p < 0.001) as compared to SC twins. Conclusions ART twin fetuses present signs of fetal cardiac remodeling and dysfunction. These changes are similar to those observed in ART singletons and reinforce the concept of fetal cardiac programming in ART. These results open opportunities for early detection and intervention in infants conceived by ART.