Predictors of repeat Chlamydia trachomatis infections diagnosed by DNA amplification testing among inner city females 2001; 77:26-32
All young women up to the age of 25 should be screened for chlamydial infection at least twice a year, finds research in Sexually Transmitted Infections.
Chlamydia is passed on during sex, and is a major cause of infertility in women among whom it is frequently symptomless. The UK government is known to be considering including chlamydia screening in its national screening programme, but is as yet unsure how often and what age group to screen.
Almost 4000 sexually active women between 12 and 60 were tested for chlamydia infection when they attended sexual health, family planning, or school health centres in Baltimore, USA. The study ran for 33 months up to September 1996, during which time almost 12000 visits were made.
The results showed that chlamydia was more than four times as common in women under the age of 25 as it was in older women. Almost one in three of the young women were infected with chlamydia compared with fewer than one in 10 of the older age group.
Young women also took half as much time to become infected, with time to first infection seven months in more than 50 per cent of those tested; in older women it was almost 14 months. And time to re-infection was 7.6 months in over half of them compared with 11 months in the older age group. Young women were nine times as likely to be diagnosed with chlamydia more than once during the study period.
More than three quarters of all the women tested admitted to not always using a condom and over 85 per cent claimed to have had only one sexual partner in the three months preceding the clinic visit.
The authors conclude that age below 25 is the most effective predictor of chlamydial infection, and that is more reliable than previous infections, condom use, or numbers of partners. Screening twice yearly, they say, would ensure that the short time to re-infection in the young age group was effectively accounted for.
Contact:
Dr Gale Burstein, Division of Adolescent and School Health, Centers for Disease Control, Atlanta, Georgia, USA. gib5@cdc.gov
Journal
Sexually Transmitted Infections