Embryonic Mortality in Relation to Ovulation Rate in the House Mouse

Abstract

1. Two series of observations were made to determine the time and amount of loss of eggs in relation to the number shed per ovary and per mouse. 2. The correlations between sides within mice for eggs shed was -0.528, for corpora lutea counts -0.436 for implantations -0.300 and for live embryos -0.111. 3. A positive linear trend of loss of fertilized eggs with increasing numbers of eggs per uterine horn has been shown to occur before implantation. 4. Possible causative mechanisms for the loss are discussed in relation to observations on embryonic mortality previously reported by other workers.