Archives of Gynecology and Obstetrics

, Volume 283, Issue 4, pp 717–721 | Cite as

Group B streptococci colonization in pregnant women: risk factors and evaluation of the vaginal flora

  • Talita T. Rocchetti
  • Camila Marconi
  • Vera L. M. Rall
  • Vera T. M. Borges
  • José E. Corrente
  • Márcia G. da Silva
Materno-fetal Medicine



To determine the prevalence of group B streptococci (GBS) in our population, and to assess the association between risk factors and vaginal flora with maternal rectovaginal colonization.


Samples were obtained from 405 patients between 35 and 37 weeks of gestation. Swabs from the vaginal and perianal regions were cultured in Todd Hewitt and subcultured in blood agar. Colonies suggestive of GBS were submitted to catalase and CAMP test. The vaginal flora was evaluated on Gram stain vaginal smears. Socio-demographic and obstetric data were obtained by designed form. Considering maternal GBS colonization as the response variable, a logistic regression model was fitted by the stepwise method with quantitative and qualitative explanatory variables.


The prevalence of GBS colonization was 25.4%. The most frequent vaginal flora abnormalities were cytolytic vaginosis (11.3%), followed by bacterial vaginosis (10.9%), candidosis (8.2%) and intermediate vaginal flora II (8.1%). Logistic regression analysis revealed that maternal age, number of sexual intercourse/week, occurrence of previous spontaneous abortion, presence of candidosis and cytolytic vaginosis were associated with streptococcal colonization.


The prevalence of GBS is high in pregnant women and is associated with sexual intercourse frequency, previous spontaneous abortion and the presence of candidosis or cytolytic vaginosis.


Group B streptococci Pregnancy Vaginal flora Risk factors 



The authors are thankful to Fundação de Amparo a Pesquisa do Estado de São Paulo (FAPESP) for providing financial support to this work (grant 06/55307-0 and 07/51704-7).

Conflict of interest statement

We declare that we have no conflict of interest.


  1. 1.
    Schrag SJ, Zywicki S, Farley MM et al (2000) Group B streptococcal disease in the era of intrapartum antibiotic prophylaxis. N Engl J Med 342:15–20PubMedCrossRefGoogle Scholar
  2. 2.
    Schuchat A (1998) Epidemiology of group B streptococcal disease in the United States: shifting paradigms. Clin Microbiol Rev 11:497–513PubMedGoogle Scholar
  3. 3.
    Winn HN (2007) Group B streptococcus infection in pregnancy. Clin Perinatol 34:387–392. doi: 10.1016/j.clp.2007.03.012 PubMedCrossRefGoogle Scholar
  4. 4.
    Yancey MK, Duff P, Clark P, Kurtzer T, Frentzen BH, Kubilis P (1994) Peripartum infection associated with vaginal group B streptococcal colonization. Obstet Gynecol 84:816–819PubMedGoogle Scholar
  5. 5.
    Tyrrel GL, Senzilet LD, Spika JS et al (2000) Invasive disease due to group B streptococcal infection in adults: results from a Canadian, population based, active laboratory surveillance study-1996. J Infect Dis 182:168–173. doi: 10.1086/315699 CrossRefGoogle Scholar
  6. 6.
    Boyer KM, Gotoff SP (1985) Strategies for chemoprophylaxis of GBS early-onset infections. Antibiot Chemother 35:267–280PubMedGoogle Scholar
  7. 7.
    Schuchat A (1995) Epidemiology of group B streptococcal disease in newborns: a global perspective on prevention. Biomed Pharmacother 49:19–25PubMedCrossRefGoogle Scholar
  8. 8.
    Prevention of perinatal group B streptococcal disease: a public health perspective. Centers for Disease Control and Prevention (1996) MMWR Recomm Rep 45:1–24Google Scholar
  9. 9.
    Baltimore RS (2007) Consequences of prophylaxis for group B streptococcal infections of the neonate. Semin Perinatol 31:33–38. doi: 10.1053/j.semperi.2007.01.005 PubMedCrossRefGoogle Scholar
  10. 10.
    Yücesoy G, Calişkan E, Karadenizli A et al (2004) Maternal colonisation with group B streptococcus and effectiveness of a culture-based protocol to prevent early-onset neonatal sepsis. Int J Clin Pract 58:735–739. doi: 10.1111/j.1368-5031.2004.00025.x PubMedCrossRefGoogle Scholar
  11. 11.
    Gavino M, Wang E (2007) A comparison of a new rapid real-time polymerase chain reaction system to traditional culture in determining group B streptococcus colonization. Am J Obstet Gynecol 197:388.e1–4. doi: 10.1016/j.ajog.2007.06.016 PubMedCrossRefGoogle Scholar
  12. 12.
    Regan JA, Klebanoff MA, Nugent RP (1991) The epidemiology of group B streptococcal colonization in pregnancy. Vaginal Infections and Prematurity Study Group. Obstet Gynecol 77:604–610PubMedGoogle Scholar
  13. 13.
    Persson K, Bjerre B, Hansson H, Forsgren A (1981) Several factors influencing the colonization of group B streptococci—rectum probably the main reservoir. Scand J Infect Dis 13:171–175PubMedGoogle Scholar
  14. 14.
    Foxman B, Gillespie BW, Manning SD, Marrs CF (2007) Risk factors for group B streptococcal colonization: potential for different transmission systems by capsular type. Ann Epidemiol 17:854–862. doi: 10.1016/j.annepidem.2007.05.014 PubMedCrossRefGoogle Scholar
  15. 15.
    Davies HD, Adair CE, Partlow ES, Sauve R, Low DE, McGeer A (1999) Two-year survey of Alberta laboratories processing of antenatal group B streptococcal (GBS) screening specimens: implications for GBS screening programs. Diagn Microbiol Infect Dis 35:169–176PubMedCrossRefGoogle Scholar
  16. 16.
    Romero R, Chaiworapongsa T, Kuivaniemi H, Tromp G (2004) Bacterial vaginosis, the inflammatory response and the risk of preterm birth: a role for genetic epidemiology in the prevention of preterm birth. Am J Obstet Gynecol 190:1509–1519. doi: 10.1016/j.ajog.2004.01.002 PubMedCrossRefGoogle Scholar
  17. 17.
    Hillier SL, Krohn MA, Klebanoff SJ, Eschenbach DA (1992) The relationship of hydrogen peroxide-producing lactobacilli to bacterial vaginosis and genital microflora in pregnant women. Obstet Gynecol 79:369–373PubMedCrossRefGoogle Scholar
  18. 18.
    Kubota T (1998) Relationship between maternal group B streptococcal colonization and regnancy outcome. Obstet Gynecol 92:926–930PubMedCrossRefGoogle Scholar
  19. 19.
    Altoparlack U, Kadanali A, Kadanali S (2004) Genital flora in pregnancy and its association with group B streptococcal colonization. Int J Gynaecol Obstet 87:245–256. doi: 10.1016/j.ijgo.2004.08.006 CrossRefGoogle Scholar
  20. 20.
    Nugent RP, Krohn MA, Hillier SL (1991) Reliability of diagnosing bacterial vaginosis is improved by a standardized method of gram stain interpretation. J Clin Microbiol 29:297–301PubMedGoogle Scholar
  21. 21.
    Heelan JS, Struminsky J, Lauro P, Sung CJ (2005) Evaluation of a new selective enrichment broth for detection of group B streptococci in pregnant women. J Clin Microbiol 43:896–897. doi: 10.1128/JCM.43.2.896-897.2005 PubMedCrossRefGoogle Scholar
  22. 22.
    Schrag S, Gorwitz PR, Fultz-Butts K, Schuchat A (2002) Prevention of perinatal group b streptococcal disease. Revised guidelines from CDC. MMWR Recomm Rep 16:1–22Google Scholar
  23. 23.
    Moyo SR, Mudzori J, Tswana SA, Maeland JA (2000) Prevalence, capsular type distribution, anthropometric and obstetric factors of group B streptococcus (Streptococcus agalactiae) colonization in pregnancy. Cent Afr J Med 46:115–120PubMedGoogle Scholar
  24. 24.
    Kadanali A, Altoparlak U, Kadanali S (2005) Maternal carriage and neonatal colonisation of group B streptococcus in eastern Turkey: prevalence, risk factors and antimicrobial resistance. Int J Clin Pract 59:437–440. doi: 10.1111/j.1368-5031.2005.00395.x PubMedCrossRefGoogle Scholar
  25. 25.
    McDonald HM, Chambers HM (2000) Intrauterine infection and spontaneous midgestation abortion: is the spectrum of microorganisms similar to that in preterm labor? Infect Dis Obstet Gynecol 8:220–227. doi: 10.1155/S1064744900000314 PubMedCrossRefGoogle Scholar
  26. 26.
    Turrentine M, Ramirez M (2007) Prevalence of group B streptococci (GBS) colonization in subsequent pregnancies. Am J Obstet Gynecol 10:S69. doi: 10.1016/j.ajog.2007.10.222 CrossRefGoogle Scholar
  27. 27.
    Klein LL, Gibbs RS (2005) Infection and preterm birth. Obstet Gyneco Clin North Am 2:397–410. doi: 10.1016/j.ogc.2005.03.001 CrossRefGoogle Scholar
  28. 28.
    Honig E, Mouton JW, Van der Meijden WI (2002) Epidemiology of vaginal colonisation with group B streptococci in a sexually transmitted disease clinic. Eur J Obstet Gynecol Reprod Biol 105:177–180. doi: 10.1016/S0301-2115(02)00162-8 PubMedGoogle Scholar
  29. 29.
    Cibley LJ, Cibley LJ (1991) Cytolytic vaginosis. Am J Obstet Gynecol 165:1245–1249PubMedGoogle Scholar

Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Talita T. Rocchetti
    • 1
  • Camila Marconi
    • 1
  • Vera L. M. Rall
    • 2
  • Vera T. M. Borges
    • 3
  • José E. Corrente
    • 4
  • Márcia G. da Silva
    • 1
  1. 1.Department of Pathology, Botucatu Medical SchoolSão Paulo State University, UNESPBotucatuBrazil
  2. 2.Department of Microbiology and Immunology, Institute of BiosciencesSão Paulo State University, UNESPBotucatuBrazil
  3. 3.Department of Gynecology and Obstetrics, Botucatu Medical SchoolSão Paulo State University, UNESPBotucatuBrazil
  4. 4.Department of Biostatistics, Institute of BiosciencesSão Paulo State University, UNESPBotucatuBrazil

Personalised recommendations