The aim of the study was to assess the effect of guinea pig fetal position on the righting reflex from a supine to prone position using ultrasound examination. Experimental and control group were formed, each encompassing 20 pregnant females with 50 fetuses from the 31st to 66th day of gestation. During ultrasound examination, the fetuses from the experimental group
were brought into a supine position relative to gravity by placing the dams in the appropriate position. In the control group fetuses were examined for changes in position irrespective of gravity as well as for changes in position after having been brought into a prone position relative to gravity. Comparison of the experimental and the control group showed that experimental group fetuses in the oldest bracket rotated successfully to a prone position more frequently than at other ages. The observed fetal movements indicate that the fetus changes its position using the contact-righting reflex
