Pregnancies and Time to Pregnancy in Women With and Without a Previous Chlamydia trachomatis Infection.

Background: A Chlamydia trachomatis infection (chlamydia) can result in tubal factor infertility in women. To assess if this association results in fewer pregnant women, we aimed to assess pregnancy incidences and time to pregnancy among women with a previous chlamydia infection compared with women without one and who were participating in the Netherlands Chlamydia Cohort Study (NECCST).

Methods: The NECCST is a cohort of women of reproductive age tested for chlamydia in a chlamydia screening trial between 2008 and 2011 and reinvited for NECCST in 2015 to 2016.

Chlamydia trachomatis and the Risk of Pelvic Inflammatory Disease, Ectopic Pregnancy, and Female Infertility: A Retrospective Cohort Study Among Primary Care Patients.

Background: We evaluated the risk of pelvic inflammatory disease (PID), ectopic pregnancy, and infertility in women with a previous Chlamydia trachomatis (CT) diagnosis compared with women who tested negative for CT and CT untested women, considering both targeted and incidental (ie, prescribed for another indication) use of CT-effective antibiotics.

Methods: This was a retrospective study of women aged 12-25 years at start of follow-up within the Clinical Practice Research Datalink GOLD database linked to index of multiple deprivation quintiles, 2000-2013. CT test status and antibiotic use were determined in a time-dependent manner.

Relation between infection and pelvic inflammatory disease, ectopic pregnancy and tubal factor infertility in a Dutch cohort of women previously tested for chlamydia in a chlamydia screening trial.

Objectives: A better understanding of infection (chlamydia)-related sequelae can provide a framework for effective chlamydia control strategies. The objective of this study was to estimate risks and risk factors of pelvic inflammatory disease (PID), ectopic pregnancy and tubal factor infertility (TFI) with a follow-up time of up until 8 years in women previously tested for chlamydia in the Chlamydia Screening Implementation study (CSI) and participating in the Netherlands Chlamydia Cohort Study (NECCST).

Methods: Women who participated in the CSI 2008-2011 (n=13 498) were invited in 2015-2016 for NECCST.

National prevalence estimates of chlamydia and gonorrhoea in the Netherlands.

Objectives: National prevalence estimates of (chlamydia) and (gonorrhoea) are important for providing insights in the occurrence and control of these STIs. The aim was to obtain national prevalence estimates for chlamydia and gonorrhoea and to investigate risk factors associated with infection.

Methods: Between November 2016 and January 2017, we performed a national population-based cross-sectional probability sample survey among men and women aged 18-34 years in the Netherlands.

STIs in sex partners notified for chlamydia exposure: implications for expedited partner therapy.

Objectives: Expedited partner therapy (EPT) may reduce chlamydia reinfection rates. However, the disadvantages of EPT for chlamydia include missing the opportunity to test for other STIs and unnecessary use of antibiotics among non-infected partners. As part of a larger study that investigated the feasibility of EPT in the Netherlands, we explored the frequency of STI among a potential EPT target population of chlamydia-notified heterosexual men and women attending STI clinics for testing.

Partner notification and partner treatment for chlamydia: attitude and practice of general practitioners in the Netherlands; a landscape analysis.

Background: Chlamydia prevalence remains high despite scaling-up control efforts. Transmission is not effectively interrupted without partner notification (PN) and (timely) partner treatment (PT). In the Netherlands, the follow-up of partners is not standardized and may depend on GPs' time and priorities.

Incidence and persistence of carcinogenic genital human papillomavirus infections in young women with or without Chlamydia trachomatis co-infection.

We assessed whether infection with chlamydia increases the incidence of carcinogenic human papillomavirus (HPV) infections and if HPV persistence is affected by chlamydia co-infection. For 1982 women (16-29 years-old) participating in two consecutive rounds of a chlamydia screening implementation trial, swabs were polymerase chain reaction tested to detect chlamydia and 14 carcinogenic HPV genotypes. HPV type-specific incidence and persistence rates were stratified for chlamydia positivity at follow-up.

Comparison of STI-related consultations among ethnic groups in the Netherlands: an epidemiologic study using electronic records from general practices.

Background: Currently, surveillance of sexually transmitted infections (STIs) among ethnic minorities (EM) in the Netherlands is mainly performed using data from STI centers, while the general practitioner (GP) is the most important STI care provider. We determined the frequency of STI-related episodes at the general practice among EM, and compared this with the native Dutch population.

Methods: Electronic medical records from 15-to 60-year-old patients registered in a general practice network from 2002 to 2011 were linked to the population registry, to obtain (parental) country of birth.

Chlamydia screening is not cost-effective at low participation rates: evidence from a repeated register-based implementation study in The Netherlands.

Objective: In three pilot regions of The Netherlands, all 16-29 year olds were invited to participate in three annual rounds of Chlamydia screening. The aim of the present study is to evaluate the cost-effectiveness of repeated Chlamydia screening, based on empirical data.

Methods: A mathematical model was employed to estimate the influence of repeated screening on prevalence and incidence of Chlamydial infection.

Urogenital Chlamydia trachomatis strain types, defined by high-resolution multilocus sequence typing, in relation to ethnicity and urogenital symptoms among a young screening population in Amsterdam, The Netherlands.

Introduction: Previous studies found conflicting results regarding associations between urogenital Chlamydia trachomatis infections and ethnicity or urogenital symptoms among at-risk populations using either ompA-based genotyping or high-resolution multilocus sequence typing (MLST). This study applied high-resolution MLST on samples of individuals from a selected young urban screening population to assess the relationship of C. trachomatis strain types with ethnicity and self-reported urogenital symptoms.

Genital chlamydia prevalence in Europe and non-European high income countries: systematic review and meta-analysis.

Background: Accurate information about the prevalence of Chlamydia trachomatis is needed to assess national prevention and control measures.

Methods: We systematically reviewed population-based cross-sectional studies that estimated chlamydia prevalence in European Union/European Economic Area (EU/EEA) Member States and non-European high income countries from January 1990 to August 2012. We examined results in forest plots, explored heterogeneity using the I² statistic, and conducted random effects meta-analysis if appropriate.

Chlamydia trachomatis Antibody Testing in Vaginal Mucosal Material versus Blood Samples of Women Attending a Fertility Clinic and an STI Clinic.

Background. Chlamydia infections often follow an asymptomatic course but may damage the reproductive tract. Chlamydia antibodies in serum are used as markers for past infections and can relate to tubal pathology and infertility.

Consultations for sexually transmitted infections in the general practice in the Netherlands: an opportunity to improve STI/HIV testing.

Objectives: In the Netherlands, sexually transmitted infection (STI) care is provided by general practitioners (GPs) as well as by specialised STI centres. Consultations at the STI centres are monitored extensively, but data from the general practice are limited. This study aimed to examine STI consultations in the general practice.

Detection of anorectal and cervicovaginal Chlamydia trachomatis infections following azithromycin treatment: prospective cohort study with multiple time-sequential measures of rRNA, DNA, quantitative load and symptoms.

Background: Determination of Chlamydia trachomatis (Ct) treatment success is hampered by current assessment methods, which involve a single post-treatment measurement only. Therefore, we evaluated Ct detection by applying multiple laboratory measures on time-sequential post-treatment samples.

Methods: A prospective cohort study was established with azithromycin-treated (1000 mg) Ct patients (44 cervicovaginal and 15 anorectal cases).

Use of Chlamydia trachomatis high-resolution typing: an extended case study to distinguish recurrent or persistent infection from new infection.

Objectives: Repeated infections of Chlamydia trachomatis may be new infections or persistent infections due to treatment failure or due to unresolved infections in sexual partners. We aimed to establish the value of using high-resolution multilocus sequence typing (CT-MLST) to discriminate repeated C trachomatis infections.

Methods: Paired C trachomatis positive samples (baseline (T0) and after 6 months (T1)) were selected from two Dutch screening implementation studies among young heterosexual people.

[Gonococci change more quickly than prescribing practices; resistance to frequently prescribed antibiotics].

Gonococcal resistance to antibiotics is increasing worldwide. In patients tested in Dutch STI clinics in 2009, gonococcal resistance to ciprofloxacin was over 50%. Ceftriaxone, a third-generation cephalosporin, has been the first-choice medication since 2004.

Retesting for genital Chlamydia trachomatis among visitors of a sexually transmitted infections clinic: randomized intervention trial of home- versus clinic-based recall.

Background: Reinfections of Chlamydia trachomatis (Ct) are common. In a two-armed intervention study at an urban STI clinic in the Netherlands, heterosexual Ct-positive visitors received an invitation for retesting after 4-5 months. Interventions were either home-based sampling by mailed test-kit, or clinic-based testing without appointment.

Effects of population based screening for Chlamydia infections in the Netherlands limited by declining participation rates.

Background: A large trial to investigate the effectiveness of population based screening for chlamydia infections was conducted in the Netherlands in 2008-2012. The trial was register based and consisted of four rounds of screening of women and men in the age groups 16-29 years in three regions in the Netherlands. Data were collected on participation rates and positivity rates per round.

Effectiveness of yearly, register based screening for chlamydia in the Netherlands: controlled trial with randomised stepped wedge implementation.

Objective: To evaluate the effectiveness of register based, yearly chlamydia screening.

Design: Controlled trial with randomised stepped wedge implementation in three blocks.

Setting: Three regions of the Netherlands: Amsterdam, Rotterdam, and South Limburg.

Keeping participants on board: increasing uptake by automated respondent reminders in an Internet-based chlamydia screening in the Netherlands.

Background: Effectiveness of Chlamydia screening programs is determined by an adequate level of participation and the capturing of high-risk groups. This study aimed to evaluate the contribution of automated reminders by letter, email and short message service (SMS) on package request and sample return in an Internet-based Chlamydia screening among people aged 16 to 29 years in the Netherlands.

Methods: Individuals not responding to the invitation letter received a reminder letter after 1 month.

Who participates in the Dutch Chlamydia screening? A study on demographic and behavioral correlates of participation and positivity.

Background: In the Netherlands, an Internet-based Chlamydia Screening Implementation was initiated in 3 regions, aiming to reduce population prevalence by annual testing and treatment of people aged 16 to 29 years. We studied who was reached in the first screening round by relating participation and chlamydia positivity to sociodemographic and sexual risk factors.

Methods: Data from the 2008/2009 screening round were analyzed (261,025 screening invitations, 41,638 participants).

Systematic selection of screening participants by risk score in a Chlamydia screening programme is feasible and effective.

Objectives: Systematic screening for Chlamydia trachomatis by individual invitation can be optimised by filtering participants on risk profile, excluding people at no or low risk. The authors investigated this technique in a large-scale chlamydia screening programme in The Netherlands in one rural region where relatively low prevalence was expected (<2%).

Methods: Invitees were alerted by personal letter to log in to http://www.

Chlamydia infection, pelvic inflammatory disease, ectopic pregnancy and infertility: cross-national study.

Objectives: To describe, using routine data in selected countries, chlamydia control activities and rates of chlamydia infection, pelvic inflammatory disease (PID), ectopic pregnancy and infertility and to compare trends in chlamydia positivity with rates of PID and ectopic pregnancy.

Methods: Cross-national comparison including national data from Australia, Denmark, the Netherlands, New Zealand, Sweden and Switzerland. Routine data sources about chlamydia diagnosis and testing and International Classification of Disease-10 coded diagnoses of PID, ectopic pregnancy and infertility in women aged 15-39 years from 1999 to 2008 were described.