Maternal Chlamydia trachomatis Infections and Preterm Births in a University Hospital in Vitoria, Brazil

BACKGROUND Preterm birth (PTB) is a major determinant of neonatal morbimortality with adverse consequences for health. The causes are multifactorial, with intrauterine infection probably explaining most of these outcomes. It is believed that infection with Chlamydia trachomatis (CT) is also involved in PTB and premature rupture of membranes. OBJECTIVES To evaluate the prevalence of and associated factors for CT among cases of PTB attended at a University Hospital in Vitoria, Brazil. METHODS A cross-sectional study performed among parturient who had preterm birth from June 2012 to August 2013 in Vitoria, Brazil. Participants answered a questionnaire including demographic, behavioral, and clinical data. A sample of urine was collected and screened for CT using polymerase chain reaction. Chi-square tests were used for proportion differences and Student's-t tests and variance analysis were used for testing differences between mean values. Odds ratio was used as a measure of association with a 95% confidence interval. RESULTS The prevalence of PTB during the period of the study was 26% and the prevalence of CT among them was 13.9%. A total of 31.6% pregnant women were younger than 25 years old and women infected by CT were even younger than women not infected by CT (p = 0.022). Most of them (76.2%) were married or had a living partner, and CT infection was more frequent among the single ones (p = 0.018); 16.7% of women reported their first sexual intercourse under 14 years old. The causes of prematurity were maternal-fetal in 40.9%; rupture of the membranes in 29.7% and premature labor in 29.4%. In multivariate analysis, being married was a protective factor for infection [OR = 0.48 (95%CI:0.24-0.97)]. None of the other characteristics were associated with CT infection. CONCLUSIONS This study shows a high prevalence of CT infection among parturient who have preterm birth. This high prevalence highlight the need for defining screening strategies focused on young pregnant women in Brazil.