Feasibility and acceptance of cervicovaginal self-sampling within the German National Cohort (Pretest 2)

Within the German National Cohort (GNC) 100,000 adult women in Germany will be comprehensively interviewed and examined. While women's health is addressed in the basic interview, direct detection of cervicovaginal microbial colonisation or infection is not part of the examination protocol. In a pilot project the feasibility of female study participants of the GNC collecting a cervicovaginal lavage at home without having to involve a gynecologist or other medical personnel was thus investigated. The ability of the procedure to detect vaginal microbes and conditions including human papillomavirus (HPV), Chlamydia trachomatis and bacterial vaginosis (BV) were also explored.

This cross-sectional study was conducted in two study centers (Hamburg and Hanover) of the GNC during Pretest 2 in 2012 as an add-on module to the main program of the National Cohort. Participants were randomly selected through the population registration office. After providing written informed consent at the study center, participants self-collected a cervicovaginal lavage (Delphi Screener™) at home following written instructions. Participants mailed samples and acceptability questionnaires to the laboratory and the study center, respectively. Acceptability of self-sampling was categorized as consent, partial consent and rejection. The samples were analyzed by multiplex HPV genotyping for the presence of 27 mucosal HPV subtypes. To detect other pathogens "Sexually Transmitted Infection Profiling" (STIP) was used, a novel multiplex polymerase chain reaction (PCR) for various vaginally occurring pathogens/conditions coupled with subsequent bead-based Luminex(®) hybridization. Human beta-globin and DNA polymerase alpha (PolA) sequences were used as positive controls for the detection of human DNA during HPV detection and STIP, respectively.

The participation based on the proportion of all women in Pretest 2 who could take part in the add-on Pretest 2 was 67.3 % (109 out of 162). The age of participants ranged from 20 to 69 years. The self-reported median duration of the collection of the lavage was 5 min. Analysis of the questionnaires (n = 108) revealed that the self-sampling of a cervicovaginal lavage was acceptable to 98 % of women (106 out of 108), and considered to be easy by 89 % (96 out of 108) as well as user-friendly by 96 % of the women (104 out of 108). Human beta-globin and PolA as markers for human DNA and sample quality were detected in all samples analyzed while HPV as a marker for pathogen detectability was identified in 18 out of 109 samples. Of the 107 samples tested with STIP as a second marker for pathogen detectability, 5 samples were excluded from statistical analyses on bacterial colonization because of signs in the laboratory results of the use of antibiotics. For the computation of the possible occurrence of bacterial vaginosis and candidiasis 7 and 8 samples, respectively, were excluded because of low signal intensities resulting in an evaluation of 95 or 94 samples, respectively. Ureaplasma parvum was detected in 22 out of 102 samples, BV in 14 out of 95 samples and candidiasis in 13 out of 94 samples. Chlamydia trachomatis was not detected in any sample.

The feasibility study on cervicovaginal self-sampling indicates that this form of biosampling was very well accepted within the framework of the GNC and feasible in terms of pathogen detection. Its further application in the GNC would allow investigation of transience and persistence, or long-term effects of vaginal (co)infections and colonization.