[1] Inst Natl Sante Publ Quebec, Direct Risques Biol Environm & Occupat, Montreal, PQ H2P 1E2, Canada
[2] Royal Hosp Women, Dept Microbiol & Infect Dis, Carlton, Vic, Australia
[3] Univ Melbourne, Dept Obstet & Gynaecol, Melbourne, Vic, Australia
[4] Natl Inst Publ Hlth, Cuernavaca, Morelos, Mexico
[5] Univ Washington, Dept Epidemiol, Seattle, WA 98195 USA
[6] Univ New Mexico, Dept Mol Genet & Microbiol, Albuquerque, NM 87131 USA
[7] Univ New Mexico, Dept Obstet & Gynecol, Albuquerque, NM 87131 USA
[8] Natl Res Ctr, Grp Saludcoop, Bogota, Colombia
[9] Dartmouth Med Sch, Norris Cotton Canc Ctr, Dept Obstet & Gynecol, Hanover, NH USA
[10] Dartmouth Med Sch, Norris Cotton Canc Ctr, Dept Community & Family Med, Hanover, NH USA
[11] Med Univ Vienna, Womens Hlth Clin, Dept Gynecol & Obstet, Vienna, Austria
[12] Univ Hong Kong, Dept Obstet & Gynecol, Hong Kong, Peoples R China
[13] Med Coll Georgia, Dept Family Med, Augusta, GA 30912 USA
[14] Med Coll Georgia, Dept Obstet & Gynecol, Augusta, GA 30912 USA
[15] Merck Res Labs, West Point, PA USA