THE EFFECT OF ULTRASOUND EXPOSURE IN-UTERO ON THE DEVELOPMENT OF THE FETAL MOUSE TESTIS - ADULT CONSEQUENCES

The effects of exposure in utero to 1 MHz, continuous-wave ultrasound on adult growth and testicular development in the mouse was investigat ed. The spatial peak temporal average intensity (I-SPTA) employed rang ed from 1 to 10 W/cm(2), with exposure durations (t) of 200 s to 20 s. Exposures were made on days 9, 12 or 15 of gestation. Results showed an increase in postpartum deaths, an increase in the number of stillbi rths, and a decrease in litter size when I-2 greater than or equal to 1125 W-2 s/cm(4), such that there was significant loss of pups. Birthw eights of pups from nearly all dosage groups was significantly lower t han that of the sham or cage control groups. Results also showed that males exposed to ultrasound in utero had decreased testis size and dec reased daily sperm production ranging from 9% to 30%. This study showe d that ultrasound exposure in utero is capable of disrupting fetal dev elopment and having potential subsequent effects on fertility in the a dult male.