Effects of maternal ingestion of low-dose aspirin on the fetal cardiovascular system.

OBJECTIVE: Our purpose was to assess fetal central and regional hemodynamics in normal fetuses using two-dimensional, range-gated pulsed Doppler echocardiography in pregnant women on chronic baby aspirin regimen (87 mg). STUDY DESIGN: Fifteen fetuses exposed to maternal chronic ingestion of baby aspirin were compared with 26 control fetuses. Longitudinal studies of the umbilical artery waveform and blood flow through the fetal right and left ventricles were obtained every 4 weeks during gestation in a group of fetuses exposed to daily maternal intake of 87 mg of aspirin. Pulsed Doppler waveforms were obtained below the tricuspid and mitral valves, at the level of the descending aorta (below the ductus), and at the level of the fetal renal artery as it enters the kidney. All tracings were recorded on a strip chart and analyzed with a digital light-pen and graphic overlay system. Peak systolic velocity and minimal diastolic velocity were obtained for the umbilical and fetal renal artery. Peak flow velocity and velocity time integral of the pulsed Doppler waveforms of the atrioventricular valves were calculated. Acceleration time/ejection time ratio was obtained for the descending aorta. RESULTS: No significant differences were found among the two groups in either central or regional circulation. CONCLUSION: Chronic daily maternal ingestion of baby aspirin does not significantly affect the central and regional circulation of the fetus.