0002-9378/free © 2012 Published by Mosby, Inc. OBJECTIVE: We sought to provide evidenc the prevention of preterm birth (PTB). METHODS: Relevant documents, in part PubMed (US National Library of Medicine, 19 in English, which evaluate the effectiveness o gens evaluated were, in particular, vaginal pr caproate. Additionally, the Cochrane Library, through review of the above were utilized to accor...