Abstract:
Fetal hemorrhages were observed when late term pregnant female mice were exposed to a lithotripter field with peak positive pressures as low as 1 MPa. On the 18th day of gestation, the abdomens of pregnant mice were exposed to 200 pulses from a piezoelectric lithotripter delivered at a rate of ~ 1 Hz. Hemorrhages occurred in the exposed fetuses most often near bony and cartilagenous tissues---head, limbs, and ribs---while soft tissues such as the liver, intestine, and stomach were relatively free of hemorrhage. Thresholds for these effects were < 1 MPa.