Spontaneous Resolution of Asymptomatic Chlamydia trachomatis in Pregnancy

OBJECTIVE: We sought to estimate the rate of spontaneous resolution of asymptomatic Chlamydia trachomatis in pregnancy and to evaluate factors associated with its resolution. METHODS: A cohort of women enrolled in a large multicenter randomized bacterial vaginosis antibiotic trial (metronidazole versus placebo) that, when randomly allocated, had asymptomatic C trachomatis diagnosed by urine ligase chain reaction (from frozen archival specimens) between 160/7 and 236/7 weeks were included. The urine ligase chain reaction is a highly accurate predictor of genital tract chlamydial infection. A follow-up ligase chain reaction was performed between 240/7 and 296/7 weeks. RESULTS: A total of 1,953 women were enrolled in the original antibiotic trial; 1,547 (79%) had ligase chain reaction performed both at randomization and follow-up. Women receiving antibiotics effective against Chlamydia between randomization and follow-up or having symptomatic Chlamydia infection were excluded (26 women). Of the 140 women (9%) who were diagnosed as positive via the initial ligase chain reaction assay, 61 (44%) had spontaneous resolution of Chlamydia by the follow-up ligase chain reaction assay. Factors associated with spontaneous resolution included older age (P = .02), more than 5 weeks from randomization to follow-up (P = .02), and a greater number of lifetime sexual partners (P = .02). Using a logistic regression model, maternal age and a greater-than-5-week follow-up interval remained significant; for every 5-year increase in maternal age, the odds of a positive result on the ligase chain reaction test at follow-up decreased by 40% (odds ratio 0.6; 95% confidence interval 0.4–0.9). Race, substance abuse, parity, and treatment with metronidazole were not associated with spontaneous resolution. Gram stain score and vaginal pH at randomization and follow-up also were not associated. CONCLUSION: The prevalence of asymptomatic C trachomatis in pregnancy was 9%; infection resolved spontaneously in almost half of these women. The association of older age and increasing time interval to spontaneous resolution of Chlamydia is consistent with a host immune-response mechanism. LEVEL OF EVIDENCE: III

[1]  W. Levine,et al.  SEXUALLY TRANSMITTED DISEASES TREATMENT GUIDELINES 2002 , 2002, MMWR. Recommendations and reports : Morbidity and mortality weekly report. Recommendations and reports.

[2]  J J Knapik,et al.  Predictors of low physical fitness in a cohort of active-duty U.S. Air Force members. , 2001, American journal of preventive medicine.

[3]  J. Carey,et al.  Metronidazole to prevent preterm delivery in pregnant women with asymptomatic bacterial vaginosis , 2001 .

[4]  Ichael,et al.  Metronidazole to prevent preterm delivery in pregnant women with asymptomatic bacterial vaginosis. National Institute of Child Health and Human Development Network of Maternal-Fetal Medicine Units. , 2000, The New England journal of medicine.

[5]  N. Low,et al.  Screening for chlamydial infections and the risk of ectopic pregnancy in a county in Sweden: ecological analysis. , 1998, BMJ.

[6]  G. Makulowich.  HIV and STD Prevention Update. CDC Chlamydia Screening Program. , 1998, AIDS patient care and STDs.

[7]  E. Hook,et al.  Spontaneous Clearance of Chlamydia trachomatis Infection in Untreated Patients , 1997, Sexually transmitted diseases.

[8]  W. Andrews,et al.  Detection of genitourinary tract Chlamydia trachomatis infection in pregnant women by ligase chain reaction assay , 1997, Obstetrics and gynecology.

[9]  W. M. Mac Kenzie,et al.  Recurrent chlamydial infections increase the risks of hospitalization for ectopic pregnancy and pelvic inflammatory disease. , 1997, American journal of obstetrics and gynecology.

[10]  P. Mårdh,et al.  A Cost-effectiveness Analysis of Screening and Treatment for Chlamydia trachomatis Infection in Asymptomatic Women , 1996, Annals of Internal Medicine.

[11]  R. Morrison,et al.  Gene knockout mice establish a primary protective role for major histocompatibility complex class II-restricted responses in Chlamydia trachomatis genital tract infection , 1995, Infection and immunity.

[12]  Helen H. Lee,et al.  Noninvasive tests for diagnosis of Chlamydia trachomatis infection: application of ligase chain reaction to first-catch urine specimens of women. , 1995, The Journal of infectious diseases.

[13]  Helen H. Lee,et al.  Diagnosis of Chlamydia trachomatis genitourinary infection in women by ligase chain reaction assay of urine , 1995, The Lancet.

[14]  Schachter,et al.  Ligase chain reaction to detect Chlamydia trachomatis infection of the cervix , 1994, Journal of clinical microbiology.

[15]  T. Quinn,et al.  Transmission of Chlamydia trachomatis among sex partners assessed by polymerase chain reaction. , 1993, The Journal of infectious diseases.

[16]  R. Rank,et al.  Resolution of chlamydial genital infection with antigen-specific T-lymphocyte lines , 1991, Infection and immunity.

[17]  R. Peeling,et al.  Chlamydia trachomatis: its role in tubal infertility. , 1985, The Journal of infectious diseases.

[18]  W M McCormack,et al.  Fifteen-month follow-up study of women infected with Chlamydia trachomatis. , 1979, The New England journal of medicine.