MAINTENANCE OF THE CORPUS LUTEUM AND INHIBITION OF PARTURITION IN THE RABBIT BY INJECTION OF ESTROGENIC HORMONE

Abstract

Parturition in the rabbit was delayed by continued inj. of estrogenic hormone in the latter part of pregnancy. Corpora lutea were maintained and their continued activity was shown to be the cause for the delay in parturition. If injs. were not continued, parturition was not delayed. Isolated injs. near term were followed by delivery of dead fetuses within 4 days; corpora lutea were not maintained. Doses of estrogenic hormone sufficient to delay parturition always caused death of the fetuses.