Aim:This study aims to investigate the effects of maternal asthma on fetal cardiac functions. Methods:The study was planned with 30 pregnant women who presented to a tertiary health center and were diagnosed with asthma and 60 healthy controls with similar gestational ages. The fetal echocardiographic assessment was assessed between 33 and 35 weeks of gestation with pulsed-wave Doppler (PW), M-mode, and tissue Doppler imaging (TDI). Fetal cardiac functions were compared between maternal asthma and control group. Cardiac functions were assessed according to the duration of maternal asthma diagnosis, as well. Results:Early diastolic function parameters, tricuspid E wave (p=0.001), and tricuspid E/A ratio (P=0.005) were significantly lower in the group with maternal asthma. TAPSE and MAPSE values were statistically lower in the study group than in the control group; p=0.010 and p=0.012, respectively. Parameters assessed with TDI (E’, A’, S’, E/E’, and MPI’ of tricuspid valves) and global cardiac function parameters assessed with pulsed-wave Doppler like myocardial performance index (MPI) and left cardiac output (LCO) were similar between groups (p> 0.05). Although, MPI did not change between groups, and the isovolumetric relaxation time (IVRT) value was prolonged in maternal asthma cases (p=0.025). Conclusion:We found that maternal asthma disease causes alteration in fetal diastolic and early systolic cardiac functions, but the global fetal cardiac function does not change. Diastolic heart function values also varied with the duration of maternal asthma. Prospective studies are needed to compare fetal cardiac functions with additional patient groups according to disease severity and type of medical treatment.