Krauss-Silva L, Moreira ME, Alves MB, Rezende MR, Braga A, Camacho KG, Batista MR, Savastano C, Almada-Horta A, Guerra F. Randomized controlled trial of probiotics for the prevention of spontaneous preterm delivery associated with intrauterine infection: study protocol. Reproductive Health. 2010;7(14). PubMed: 20591191