The influence of ovarian sonication on fetal development in the rat

This study was undertaken to determine whether sonication of the ovaries on day 8 of pregnancy would alter fetal development in the rat. Mating was confirmed by the presence of sperm (day 1 of gestation) in the vaginal smear, and the rats were grouped and treated on day 8 as follows: Group I (controls) had both ovaries surgically exposed to sonic gel for 10 min/ovary; group II received 10 watts/cm 2 temporal peak intensity of pulsed ultrasound through the body wall for 10 min/ovary; group III received 100 watts/cm 2 in a similar manner as group II; group IV was treated the same as group III except the ultrasound was applied directly to the surgically exposed ovaries. The frequency employed was 1.9 mHz. The animals were sacrificed on days 15–17, implantation sites and resorptions were counted, and fetal viability was determined. There were no statistically significant differences in the percentage of resorptions among any of the groups. The data indicated that the ovaries were functional with regard to fetal development.