Prevalence of Chlamydia and Neisseria gonorrhoeae infections in pregnant women in six Brazilian cities

PURPOSE: This paper has aimed at estimating the prevalence of infections by Chlamydia trachomatis and by Neisseria gonorrhoeae in pregnant women from six Brazilian cities, identifying its association with socio-economical and demographic variables. METHODS: This study has been part of a multicentric nationwide transversal research, with samples of pregnant women attended from 2004 to 2005 in basic attention pre-natal services from six Brazilian cities (Manaus, Fortaleza, Goiania, Rio de Janeiro, Sao Paulo and Porto Alegre). Cervico-vaginal samples have been collected from all the pregnant women, and have afterwards been submitted to the hybrid capture technique in order to identify chlamydia and gonococcus. Socio-demographic, medical, sexual and obstetric information have been collected through specific questionnaires. The Odds Ratio (OR) has been used to evaluate risk factors associated to infection by gonorrhea and chlamydia. Statistical analysis has been done with the t-Student, chi(2) and Fisher's exact tests. RESULTS: Three thousand and three pregnant women with an average age of 23.8 years old (+/- 6.9) took part in the study. Infection prevalence by chlamydia and gonococcus were 9.4 and 1.5, respectively. Ten per cent of the pregnant women with chlamydia have presented gonococcus simultaneously. The risk of presenting one of those infections was two times higher for the women under 20. The infection main predictors have been: age under 20, race/black, single/separated and report of over one partner in the previous year. CONCLUSIONS: This study has observed high prevalence of infection by Chlamydia trachomatis and by Neisseria gonorrhoeae in Brazilian pregnant women. The main risk factor for the infection has been to be under 20 years old.