Reproductive system tumors in mice exposed to various types of fat perinatally.

Studies of human populations have produced conflicting evidence on whether increased intake of dietary fat increases the risk of female reproductive system cancer. Some animal studies have indicated that the perinatal period of development is the sensitive time for this effect. Since type of fat has been linked to cancer risk, the question is raised as to whether the perinatal period is also sensitive to type of fat. To test this question, mice were exposed perinatally to either corn oil, fish oil, olive oil, or lard, and tumor frequencies were determined for female offspring at the end of their lifespan. No significant differences were found between the 4 groups with respect to reproductive system tumor frequency. Also, there were no significant differences with respect to the variables of lifespan or body weight. Thus, there was no indication that the perinatal period of development was sensitive to type of fat with respect to carcinogenic effects.