Recent investigations have shown decreased fetal weight in pregnant animals who were exercised regularly during pregnancy (Gilbert; Nelson; Longo, 1979; Terada, 1974). The purpose of this experimental study was to investigate fetal weight gain and measure blood flow in pregnant guinea pigs who were exercised 45 minutes per day; and thus answer the hypothesis that prolonged maternal exercise will cause decreased weight gain and decreased placental blood flow during pregnancy.

Twenty pregnant guinea pigs were exercised 15 minutes three times daily from 10 days gestation to approximately 60-62 days gestation (67 days being term) and were compared with 19 control animals who were not exercised. Blood flow analysis via microsphere technique was taken during exercise and at rest. At near term, catheters were placed in the left femoral artery and left ventricle of the guinea pig. Radionuclide microspheres were injected into the left ventricle at rest and after three minutes of treadmill running. After disection, the organs were weighed. carbonized and placed in a gamma counter to measure microsphere concen- tration. This study showed significant decreased fetal weight, and significant blood changes as a result of maternal exercise of 45 minutes per day. After three minutes of continuous exercise, blood flow to exercising muscles increased threefold in both experimental and control animals. Blood flow to the gastrointestinal tract decreased 40 percent in the experimental group and slightly more in the control group. Uterine and spleenic blood flow decreased approximately 50 percent in both groups after three minutes of maternal exercise. Blood flow to the kidney decreased by 45 percent in the control group and 20 percent in the experi- mental group. Blood flow to the brain and heart, while demonstrating slight increases, remained relatively constant in both groups.

This study concluded that with maternal exercise of 45 minutes per day in guinea pigs, there was a significant decrease in fetal weight and decreased placental blood flow during exercise. The results of this study suggest a need for moderation in exercise during pregnancy.

LLU Discipline





Graduate School

First Advisor

Clarice W. Woodward

Second Advisor

Raymond D. Gilbert

Third Advisor

Audrey L. Burgess

Degree Name

Master of Science (MS)

Degree Level


Year Degree Awarded


Date (Title Page)




Library of Congress/MESH Subject Headings

Exertion; Rheology; Pregnancy



Page Count

vii; 45

Digital Format


Digital Publisher

Loma Linda University Libraries

Usage Rights

This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.


Loma Linda University Electronic Theses and Dissertations

Collection Website



Loma Linda University. Del E. Webb Memorial Library. University Archives