OP04.05: Effects of maternal Mediterranean diet on fetal cardiac function in high‐risk pregnancies: the IMPACT BCN trial

To investigate the effect of maternal lifestyle interventions on fetal cardiac function in high-risk pregnancies from the IMPACT BCN trial. In the IMPACT BCN trial, a parallel-group randomised clinical trial conducted at a University Hospital in Barcelona, Spain, 1221 pregnant women at high-risk for small for gestational age were randomly allocated at 19-23 weeks' gestation into three groups: promotion of Mediterranean Diet (MedDiet), a mindfulness-based stress reduction program (MBSR) or usual care. Participants in the MedDiet group received monthly individual and group educational sessions, and free provision of extra-virgin olive oil and walnuts. Comprehensive fetal echocardiography was performed at 33-34 weeks' gestation. N-terminal pro B-type natriuretic peptide (NT-proBNP) was measured in cord blood collected at delivery and considered high if above 90th centile. Fetal echocardiography and cord blood NT-proBNP were obtained in 990 pregnancies (n = 333 MedDiet, MBSR n = 311, n = 346 usual care). While fetuses from the MBSR showed similar fetal cardiac results as compared to usual care, fetuses whose mothers followed MedDiet showed higher right ventricular fractional area change (MedDiet median 30.4% (IQR 8.3) vs usual care 28.1% (8.9), p = 0.03) and thinner myocardial wall thickness (MedDiet 2.95mm (0.55) vs usual care 3.16mm (0.58), p = 0.006) as compared to usual care. The proportion of fetuses with NT-proBNP >90th centile was significantly lower in MedDiet as compared to usual care (6.4% vs. 12%, p = 0.03). MedDiet intervention during pregnancy seems to have a positive effect on fetal heart. Fetuses whose mothers followed a MedDiet intervention during pregnancy exhibited more efficient systolic function and less signs of cardiac overload than those with no intervention. Future research is warranted to elucidate the mechanism(s) underlying these findings.