Randomised controlled trial of screening for Chlamydia trachomatis to prevent pelvic inflammatory disease: the POPI (prevention of pelvic infection) trial.

OBJECTIVE: To determine whether screening and treating women for chlamydial infection reduces the incidence of pelvic inflammatory disease over the subsequent 12 months. DESIGN: Randomised controlled trial. SETTING: Common rooms, lecture theatres, and student bars at universities and further education colleges in London. PARTICIPANTS: 2529 sexually active female students, mean age 21 years (range 16-27). INTERVENTION: Participants completed a questionnaire and provided self taken vaginal swabs, with follow-up after one year. Samples were randomly allocated to immediate testing and treatment for chlamydial infection, or storage and analysis after a year (deferred screening controls). MAIN OUTCOME MEASURE: Incidence of clinical pelvic inflammatory disease over 12 months. RESULTS: Baseline prevalence of chlamydia was 5.4% (68/1254) in screened women and 5.9% (75/1265) in controls. 94% (2377/2529) of women were followed up after 12 months. The incidence of pelvic inflammatory disease was 1.3% (15/1191) in screened women compared with 1.9% (23/1186) in controls (relative risk 0.65, 95% confidence interval 0.34 to 1.22). Seven of 74 control women (9.5%, 95% confidence interval 4.7% to 18.3%) who tested positive for chlamydial infection at baseline developed pelvic inflammatory disease over 12 months compared with one of 63 (1.6%) screened women (relative risk 0.17, 0.03 to 1.01). However, most episodes of pelvic inflammatory disease occurred in women who tested negative for chlamydia at baseline (79%, 30/38). 22% (527/2377) of women reported being tested independently for chlamydia during the trial. CONCLUSION: Although some evidence suggests that screening for chlamydia reduces rates of pelvic inflammatory disease, especially in women with chlamydial infection at baseline, the effectiveness of a single chlamydia test in preventing pelvic inflammatory disease over 12 months may have been overestimated. Trial registration ClinicalTrials.gov NCT00115388.

Community-based trial of screening for Chlamydia trachomatis to prevent pelvic inflammatory disease: the POPI (prevention of pelvic infection) trial.

BACKGROUND: Pelvic inflammatory disease (PID) is common and can lead to tubal factor infertility, ectopic pregnancy or chronic pelvic pain. Despite major UK government investment in the National Chlamydia Screening Programme, evidence of benefit remains controversial. The main aim of this trial was to investigate whether screening and treatment of chlamydial infection reduced the incidence of PID over 12 months. Secondary aims were to conduct exploratory studies of the role of bacterial vaginosis (BV) in the development of PID and of the natural history of chlamydial infection. DESIGN: Randomised controlled trial with follow up after 12 months. SETTING NON-HEALTHCARE: Common rooms and lecture theatres at 20 universities and further education colleges in Greater London. PARTICIPANTS: 2500 sexually active female students were asked to complete a questionnaire on sexual health and provide self-administered vaginal swabs and smears. INTERVENTION: Vaginal swabs from intervention women were tested for chlamydia by polymerase chain reaction (PCR) and those infected referred for treatment. Vaginal swabs from control women were stored and analysed after a year. Vaginal smears were Gram stained and analysed for BV. MAIN OUTCOME MEASURE: Incidence of clinical PID over 12 months in intervention and control groups. Possible cases of PID will be identified from questionnaires and record searches. Confirmation of the diagnosis will be done by detailed review of medical records by three independent researchers blind to whether the woman is in intervention or control group. TRIAL REGISTRATION: Clinical Trials NCT 00115388.

Lessons learned from recruiting young female students to a randomised controlled trial of chlamydia screening.

BACKGROUND: Recruitment is a problem in many trials. Two female medical students offered to help with recruiting problems in a community-based trial of chlamydia screening to prevent pelvic inflammatory disease. We need to recruit 2500 sexually active female students and ask them to provide a self-taken low vaginal swab and complete a questionnaire with follow-up after a year. OBJECTIVES: To identify recruitment difficulties in a community-based trial of chlamydia screening and to investigate how they might be overcome. DESIGN: Descriptive study. SETTING: London South Bank and Kingston Universities. METHODS: The students observed the recruitment methods used for the first 4 months of the trial. This comprised single researchers recruiting individual women in student bars and common rooms. With the researchers they piloted a new method of group recruitment with pairs of researchers making announcements at the end of lectures after first sending out all male students and those aged>25 years. This involved extra time planning and liaising with the lecturers in advance of recruitment sessions. RESULTS: The recruitment rate had been averaging only 25 participants per week. Many students were ineligible: never been sexually active, too old, recently been tested for chlamydia. Many eligible students were reluctant to take part because of embarrassment or anxiety about providing a swab. Using a new method of group recruitment after lectures we recruited 192 participants in 2 weeks. CONCLUSION: For a study on a sensitive topic, two researchers recruiting women in groups after lectures may be a more effective and cost-effective way than individual recruitment by researchers working alone.

Bacterial vaginosis and preterm birth: a prospective community-based cohort study.

BACKGROUND: Preterm birth before 37 weeks' gestation is associated with 70% of perinatal morbidity and nearly half of long-term neurological morbidity. Hospital-based studies have shown that bacterial vaginosis is associated with preterm birth. AIM: To estimate the relative risk of preterm birth in women with and without bacterial vaginosis, detected by self-administered vaginal swab at < 10 weeks' gestation. DESIGN: Prospective cohort study. SETTING: Thirty-two general practices and five family planning clinics in South London. PARTICIPANTS: A total of 1216 women with bacterial vaginosis status established before 10 weeks' gestation, by analysis of Gram stained vaginal smears by two independent observers. METHOD: All women who did not miscarry or have a termination of pregnancy before 16 weeks' gestation were sent a brief confidential questionnaire at 16 weeks and at term asking about pregnancy outcome. Data on non-responders were obtained by searches of hospital and general practice records and by telephone calls to patients. RESULTS: Ascertainment was 87% (937/1072). The mean age of the women was 31 years. Thirteen per cent (122/925) had bacterial vaginosis and 5% (44/897) had a spontaneous preterm birth. The relative risk (RR) of preterm birth in women with bacterial vaginosis was 0.9 (95% confidence interval [CI] = 0.4 to 2.2). However, bacterial vaginosis was associated with late miscarriage at 13-23 weeks (R = 4.0, 95%CI = 1.3 to 12.1). Preterm birth was not associated with previous preterm birth, black ethnicity, age < 20 years, low social class, single marital status, or chlamydial infection. However, it was more common in women who reported smoking in pregnancy (RR = 2.9, 95% CI = 1.5 to 5.5). Of 867 responders, 552 (64%) said that providing a vaginal swab was at least as easy as providing a urine specimen. CONCLUSIONS: In this low-risk community-based cohort, bacterial vaginosis was not a strong risk factor for preterm birth.

Prevalence of Mycoplasma genitalium in early pregnancy and relationship between its presence and pregnancy outcome.

Mycoplasma genitalium is associated with cervicitis and pelvic inflammatory disease but little is known about its role in pregnancy. We investigated the prevalence of M. genitalium by polymerase chain reaction assay on urine specimens from 1216 pregnant women (mean age 31years) presenting before 10 weeks of gestation in 32 general practices. The prevalence of M. genitalium was 0.7% (6/915, 95% CI 0.1-1.2). It was more common in women aged < 20 years, women of Afro-Caribbean or black African ethnic origin, women in social classes 3-5 and single women. Only one woman with M. genitalium infection miscarried, and none of those followed up to term had a preterm birth, although the numbers were small. The low prevalence of M. genitalium infection suggests it is unlikely to be an important risk factor in adverse pregnancy outcome in healthy women in the community.

Association between bacterial vaginosis or chlamydial infection and miscarriage before 16 weeks' gestation: prospective community based cohort study.

OBJECTIVES: To assess whether bacterial vaginosis or chlamydial infection before 10 weeks' gestation is associated with miscarriage before 16 weeks. DESIGN: Prospective cohort study. SETTING: 32 general practices and five family planning clinics in south London. PARTICIPANTS: 1216 pregnant women, mean age 31, presenting before 10 weeks' gestation. MAIN OUTCOME MEASURE: Prevalence of miscarriage before 16 weeks' gestation. RESULTS: 121 of 1214 women (10.0%, 95% confidence interval 8.3% to 11.7%) miscarried before 16 weeks. 174 of 1201 women (14.5%, 12.5% to 16.5%) had bacterial vaginosis. Compared with women who were negative for bacterial vaginosis those who were positive had a relative risk of miscarriage before 16 weeks' gestation of 1.2 (0.7 to 1.9). Bacterial vaginosis was, however, associated with miscarriage in the second trimester at 13-15 weeks (3.5, 1.2 to 10.3). Only 29 women (2.4%, 1.5% to 3.3%) had chlamydial infection, of whom one miscarried (0.32, 0.04 to 2.30). CONCLUSION: Bacterial vaginosis is not strongly predictive of early miscarriage but may be a predictor after 13 weeks' gestation. The prevalence of Chlamydia was too low to assess the risk, but it is unlikely to be a major risk factor in pregnant women.

Detection of Chlamydia trachomatis infection in early pregnancy using self-administered vaginal swabs and first pass urines: a cross-sectional community-based survey.

A cross-sectional survey of 1216 newly pregnant women (mean age = 31 years) from 32 general practices and five family planning clinics was conducted to find the prevalence of chlamydial infection and to evaluate self-administered vaginal swabs and first-pass urines for detection of Chlamydia trachomatis by ligase chain reaction assay. Overall prevalence of infection was 2.4% (95% CI = 1.5 to 3.3) but in women aged less than 25 years it was 8.6% (95% CI = 4.1 to 12.9) and in pregnant teenagers it was 14.3% (95% CI = 3.7 to 24.9). In 1161 women with both swab and urine results, 25 women were positive on both specimens three on swab alone, and one on urine alone. When asked which they preferred to provide, 47% said urine, 59 swab and 48% preferred both equally. This is the first study to show that non-invasive screening in early pregnancy is feasible in the community. Although swabs detected 10% more infections, nearly half the women preferred providing urine specimens.