Incidence of Doppler regurgitant flow velocities during normal pregnancy

The incidence of regurgitant flow velocities were determined using colour flow mapping and pulse Doppler in 107 pregnant women, 55 of whom were less than 28 weeks gestation. The results were compared with 51 non-pregnant controls. The incidence of tricuspid regurgitant velocities increased from 42% in the control group to 67% at greater than or equal to 28 weeks gestation with a median peak regurgitant velocity of 1.7 ms-1. The incidence of pulmonary regurgitant velocities increased from 50% in the control group to 96% at greater than or equal to 28 weeks gestation with a median peak regurgitant velocity of 1.1 m s-1. Mitral and aortic regurgitant velocities were recorded in 27% and 2% of non-pregnant controls respectively. No statistically significant increase in left sided regurgitant velocities was evident during pregnancy. The increase in incidence of right heart regurgitant velocities may be secondary to the dilatation of the respective value orifices due to the volume loading of pregnancy.