Studies on the Detection Rate of Chlamydia trachomatis in Married and Unmarried Pregnant Women: Field Survey in Hokkaido

Chlamydia trachomatis infection in the general population has recently been attracting attention. In this regard, we examined the incidence of positive antigen in the genital organs in pregnant female women in order to investigate the prevalence of this infection. EIA (Chlamydiazyme) was performed in 5, 000 married pregnant women, and in 317 unmarried women who underwent artifical termination of pregnancy. The study was carried out between June 1986 and September 1989 in Sapporo City (3, 932 subjects), Kushiro City (328 subjects), Muroran City (280 subjects), Kitami City (357 subects), Kucchan Town (220 subjects) and Urakawa Town (200 subjects). 1. Among married pregnent women, the detection rate of C. trachomatis was 6.1%(222/3, 666) in Sapporo City, 7.3%(24/328) in Kushiro City, 6.1%(17/280) in Muroran City, 7.8%(24/306) in Kitami City, 6.8%(15/220) in Kucchan Town and 7.5%(15/200) in Urakawa Town, showing no particular difference according to the area. The overall detection rate was 6.3%(317/5, 000). 2. The rates of detection of C. trachomatis antigen by EIA were 22.9%(61/266) and 15.7%(8/15) for the unmarried women who underwent artifical termination of pregnancy in Sapporo and Kitami, respectively. Both rates were higher than those in the married pregnent women. This result suggests the prevalence of C. trachomatis among young women showing a high level of sexual activity. 3. Among married subjects, the detection rate was 21.3% for those in their late teens, 8.9% for those in their early 20s, 6.0% for those in their late 20s, 3.7% for those in their early 30s, and 2.9% for those 35 years or older; thus, the younger they were, the detection rate became elevated. The above findings show that latent epidemics of C. trachomatis infection are present to a considerable extent among young women.