The comparative effectiveness of subcutaneous administration of 20p·OH-P, pregnanolone and progesterone in oil to prolong gestation in rats was determined. As a result it was found that, while progesterone was shown to have activity, pregnanolone and 20j1-0H-P were ineffective in doses of 5 mg per day. ∗PMID: 4263519 [PubMed indexed for MEDLINE] Copyright c ©OKAYAMA UNIVERSITY MEDICAL SCHOOL Ac...