Biological and hormonal markers of chlamydia, human papillomavirus, and bacterial vaginosis among adolescents attending genitourinary medicine clinics

Chlamydia trachomatis Incidence Using Self-Reports and Serology by Gender, Age Period, and Sexual Behavior in a Birth Cohort

BACKGROUND

Although understanding chlamydia incidence assists prevention and control, analyses based on diagnosed infections may distort the findings. Therefore, we determined incidence and examined risks in a birth cohort based on self-reports and serology.

METHODS

Self-reported chlamydia and behavior data were collected from a cohort born in New Zealand in 1972/3 on several occasions to age 38 years. Sera drawn at ages 26, 32, and 38 years were tested for antibodies to Chlamydia trachomatis Pgp3 antigen using a recently developed assay, more sensitive in women (82.9%) than men (54.4%). Chlamydia incidence by age period (first coitus to age 26, 26-32, and 32-38 years) was calculated combining self-reports and serostatus and risk factors investigated by Poisson regression.

RESULTS

By age 38 years, 32.7% of women and 20.9% of men had seroconverted or self-reported a diagnosis. The highest incidence rate was to age 26, 32.7 and 18.4 years per 1000 person-years for women and men, respectively. Incidence rates increased substantially with increasing number of sexual partners. After adjusting age period incidence rates for partner numbers, a relationship with age was not detected until 32 to 38 years, and then only for women.

CONCLUSIONS

Chlamydia was common in this cohort by age 38, despite the moderate incidence rates by age period. The strongest risk factor for incident infection was the number of sexual partners. Age, up to 32 years, was not an independent factor after accounting for partner numbers, and then only for women. Behavior is more important than age when considering prevention strategies.

Chlamydia trachomatis Pgp3 Antibody Persists and Correlates with Self-Reported Infection and Behavioural Risks in a Blinded Cohort Study

Chlamydia trachomatis (Ct) serological studies in populations could help monitor changes in lifetime cumulative risk of infection. We developed a double-antigen sandwich ELISA based on the Ct-specific Pgp3 antigen, then tested blind stored sera from over 800 participants in a New Zealand birth cohort from Dunedin at ages 26, 32 and 38. The double-antigen sandwich ELISA was more sensitive than our previously characterised indirect Pgp3 ELISA. Pgp3 antibody was detected more often in women compared to men and correlated with increasing numbers of sexual partners, self-reported Ct, and younger age at sexual debut in both women and men. At age 26, 24.1% (99/411) of women were Pgp3 seropositive, as were 79.5% (35/44) of those reporting Ct infection; Pgp3 antibody persisted to age 38 in 96.5% (83/86). In men at age 26, the figures were 10.7% (47/442) and 25.0% (6/24), respectively, with high (83.9%) antibody persistence to age 38. At age 38, among those Pgp3 seropositive, 63.3% of women and 83.1% of men had not reported Ct infection. Thus, Ct-specific Pgp3 antibody was detected in most women reporting Ct infection and correlated with risk of infection in those who did not, with most infections remaining undetected. As this antibody persisted for at least twelve years in 96% of these women, serology could be used to evaluate Ct prevention programmes among women.

Human and Pathogen Factors Associated with Chlamydia trachomatis-Related Infertility in Women

Chlamydia trachomatis is the most common bacterial sexually transmitted pathogen worldwide. Infection can result in serious reproductive pathologies, including pelvic inflammatory disease, ectopic pregnancy, and infertility, in women. However, the processes that result in these reproductive pathologies have not been well defined. Here we review the evidence for the human disease burden of these chlamydial reproductive pathologies. We then review human-based evidence that links Chlamydia with reproductive pathologies in women. We present data supporting the idea that host, immunological, epidemiological, and pathogen factors may all contribute to the development of infertility. Specifically, we review the existing evidence that host and pathogen genotypes, host hormone status, age of sexual debut, sexual behavior, coinfections, and repeat infections are all likely to be contributory factors in development of infertility. Pathogen factors such as infectious burden, treatment failure, and tissue tropisms or ascension capacity are also potential contributory factors. We present four possible processes of pathology development and how these processes are supported by the published data. We highlight the limitations of the evidence and propose future studies that could improve our understanding of how chlamydial infertility in women occurs and possible future interventions to reduce this disease burden.

2015 UK national guideline for the management of infection with Chlamydia trachomatis

This guideline offers recommendations on the diagnostic tests, treatment regimens and health promotion principles needed for the effective management of Chlamydia trachomatis genital infection. It covers the management of the initial presentation, as well the prevention of transmission and future infection. The guideline is aimed at individuals aged 16 years and older presenting to healthcare professionals working in departments offering Level 3 care in sexually transmitted infections management within the UK. However, the principles of the recommendations should be adopted across all levels, using local care pathways where appropriate.

Bacterial vaginosis in pregnant adolescents: proinflammatory cytokine and bacterial sialidase profile. Cross-sectional study

CONTEXT AND OBJECTIVE

Bacterial vaginosis occurs frequently in pregnancy and increases susceptibility to sexually transmitted infections (STI). Considering that adolescents are disproportionally affected by STI, the aim of this study was to evaluate the cervicovaginal levels of interleukin (IL)-1 beta, IL-6, IL-8 and bacterial sialidase in pregnant adolescents with bacterial vaginosis.

DESIGN AND SETTING

Cross-sectional study at mother and child referral units in Belém, Pará, Brazil.

METHODS

Vaginal samples from 168 pregnant adolescents enrolled were tested for trichomoniasis and candidiasis. Their vaginal microbiota was classified according to the Nugent criteria (1991) as normal, intermediate or bacterial vaginosis. Cervical infection due to Chlamydia trachomatisand Neisseria gonorrhoeae was also assessed. Cytokine and sialidase levels were measured, respectively, using enzyme-linked immunosorbent assays and MUAN conversion in cervicovaginal lavages. Forty-eight adolescents (28.6%) were excluded because they tested positive for some of the infections investigated. The remaining 120 adolescents were grouped according to vaginal flora type: normal (n = 68) or bacterial vaginosis (n = 52). Their cytokine and sialidase levels were compared between the groups using the Mann-Whitney test (P < 0.05).

RESULTS

The pregnant adolescents with bacterial vaginosis had higher levels of IL-1 beta, IL-6 and IL-8 (P < 0.05). Sialidase was solely detected in 35 adolescents (67.2%) with bacterial vaginosis.

CONCLUSIONS

Not only IL-1 beta and sialidase levels, but also IL-6 and IL-8 levels are higher in pregnant adolescents with bacterial vaginosis, thus indicating that this condition elicits a more pronounced inflammatory response in this population, which potentially increases vulnerability to STI acquisition.

Financial incentives for increasing uptake of HPV vaccinations: a randomized controlled trial

OBJECTIVE

Uptake of human papillomavirus (HPV) vaccinations by 17- to 18-year-old girls in England is below (<35%) target (80%). This trial assesses (a) the impact of financial incentives on uptake and completion of an HPV vaccination program, and (b) whether impacts are moderated by participants' deprivation level. It also assesses the impact of incentives on decision quality to get vaccinated, as measured by attitudes toward the vaccination and knowledge of its consequences.

METHOD

One thousand 16- to 18-year-old girls were invited to participate in an HPV vaccination program: 500 previously uninvited, and 500 unresponsive to previous invitations. Girls randomly received either a standard invitation letter or a letter including the offer of vouchers worth £ 45 (€ 56; $73) for undergoing 3 vaccinations. Girls attending their first vaccination appointment completed a questionnaire assessing decision quality to be vaccinated. Outcomes were uptake of the first and third vaccinations and decision quality.

RESULTS

The intervention increased uptake of the first (first-time invitees: 28.4% vs. 19.6%, odds ratio [OR] = 1.63, 95% confidence interval [CI; 1.08, 2.47]; previous nonattenders: 23.6% vs. 10.4%, OR = 2.65, 95% CI [1.61, 4.38]) and third (first-time invitees: 22.4% vs. 12%, OR = 2.15, 95% CI [1.32, 3.50]; previous nonattenders: 12.4% vs. 3%, OR = 4.28, 95% CI [1.92, 9.55]) vaccinations. Impacts were not moderated by deprivation level. Decision quality was unaffected by the intervention.

CONCLUSIONS

Although the intervention increased completion of HPV vaccinations, uptake remained lower than the national target, which, in addition to cost effectiveness and acceptability issues, necessitates consideration of other ways of achieving it.

Gardnerella vaginalis-associated bacterial vaginosis in Bulgarian women

Background

Bacterial vaginosis (BV) is the most common cause of vaginal discharge in women of reproductive age. The purpose of this study was to determine the frequency of BV in Bulgarian pregnant and nonpregnant women from several age ranges and to compare three different laboratory methods for Gardnerella vaginalis detection in patents suffering from BV.

Methods

Between September 2011 and June 2012, 809 women of 16–40 years of age separated in two major groups: nonpregnant – 469 (355 with and 114 without symptoms) and pregnant – 340 (213 and 127 respectively) were enrolled for the study. The women underwent three different laboratory tests simultaneously: scoring of Gram staining of vaginal smear, culture, and polymerase chain reaction (PCR) assay for G. vaginalis.

Results

The microscopic method detected high frequency of BV in symptomatic (57%) whereas only a minority of asymptomatic subjects (14%) were detected. G. vaginalis-associated BV was diagnosed in approximately equal proportions when evaluated with PCR and microscopic method for both pregnant and nonpregnant women. The comparative analysis of microscopic evaluation, culture and PCR assays demonstrated greater concurrence (about 90%) between Gram staining and PCR detection for BV, than both methods compared to culture. The combination of microscopy and PCR turned out to be very reliable and repeatable for detecting G. vaginalis-associated BV.

Conclusions

This is the first comparative investigation on the epidemiology of G. vaginalis-associated BV in Bulgaria. The established highest frequency in the young Bulgarian women (21–30 years) is alarming and should be considered in prophylaxis and reproductive programmes.

Hormone-dependent bacterial growth, persistence and biofilm formation--a pilot study investigating human follicular fluid collected during IVF cycles

Human follicular fluid, considered sterile, is aspirated as part of an in vitro fertilization (IVF) cycle. However, it is easily contaminated by the trans-vaginal collection route and little information exists in its potential to support the growth of microorganisms. The objectives of this study were to determine whether human follicular fluid can support bacterial growth over time, whether the steroid hormones estradiol and progesterone (present at high levels within follicular fluid) contribute to the in vitro growth of bacterial species, and whether species isolated from follicular fluid form biofilms. We found that bacteria in follicular fluid could persist for at least 28 weeks in vitro and that the steroid hormones stimulated the growth of some bacterial species, specifically Lactobacillus spp., Bifidobacterium spp. Streptococcus spp. and E. coli. Several species, Lactobacillus spp., Propionibacterium spp., and Streptococcus spp., formed biofilms when incubated in native follicular fluids in vitro (18/24, 75%). We conclude that bacteria aspirated along with follicular fluid during IVF cycles demonstrate a persistent pattern of growth. This discovery is important since it can offer a new avenue for investigation in infertile couples.

Using financial incentives to increase initial uptake and completion of HPV vaccinations: protocol for a randomised controlled trial

BACKGROUND

HPV vaccination reduces the risk of cervical cancer. Uptake however, of the 'catch-up' campaign in England for 17-18 year old girls is below the 80% NHS target. The aim of this randomized controlled trial is to assess the impact of financial incentives on (a) the uptake and completion of an HPV vaccination programme and (b) the quality of the decisions to undertake the vaccination.

METHOD/DESIGN

One thousand (n = 1000) 16-18 year-old girls will be invited to participate in an HPV vaccination programme: Five-hundred (n = 500) will have received a previous invitation to get vaccinated but will have failed to do so (previous non-attenders) and 500 will not have previously received an invitation (first-time invitees). Girls will be randomly selected from eligible participants who are registered with a GP in areas covered by the Birmingham East and North (BEN) and Heart of Birmingham Primary Care Trusts. The two samples of girls will be randomised to receive either a standard vaccination invitation letter or an invitation letter including the offer of vouchers worth £45 for receiving three vaccinations. Girls will also complete a questionnaire to assess the quality of their decisions to be vaccinated. The primary outcome will be uptake of the 1st and 3rd vaccinations. The secondary outcome will be the quality of the decisions to undertake the vaccination, measured by assessing attitudes towards and knowledge of the HPV vaccination.

DISCUSSION

The key results will be: a) the effectiveness of financial incentives in increasing uptake of the 1st and 3rd vaccinations; b) the role of participants' socio-economic status in the moderation of the impact of incentives on uptake; and c) the impact of incentives on the quality of decisions to undertake the HPV vaccinations.

Effect of sexual activity on vaginal colonization with hydrogen peroxide-producing lactobacilli and Gardnerella vaginalis

BACKGROUND

Bacterial vaginosis is associated with sexual activity, but mechanisms for this association are unclear.

STUDY DESIGN

Cross-sectional analysis of data from women reporting sex with women who provided information on sexual behaviors as part of a study of vaginal bacteria was conducted. Vaginal bacteria were detected by semiquantitative culture. Binomial regression with log-link evaluated associations between detection of bacteria and sexual behaviors reported to occur before enrollment. Linear regression evaluated associations between these behaviors and quantity of bacteria.

RESULTS

Of the 320 women, 216 (68%) were colonized with H2O2-producing lactobacilli and 142 (44%) with Gardnerella vaginalis. Colonization with G. vaginalis was associated with >20 digital-vaginal sex acts (risk ratio, 2.01; 1.22, 3.29) or >10 toy-vaginal acts in the past 3 months (risk ratio, 1.76; 1.32, 2.36). Quantity of H2O2-producing lactobacilli was 1.3 log lower in colonized women reporting >10 acts of insertive vaginal sex-toy use in the past 3 months (95% confidence interval: -2.04, -0.56), 1.19 log lower with toy-vaginal sex in past 7 days (-1.75, -0.62), and 0.78 log lower in women sharing toys with a partner (-1.25, -0.31).

CONCLUSIONS

Vaginal insertive use and sharing of sex toys were associated with decreased quantities of H2O2-producing lactobacilli and higher risk of colonization with G. vaginalis.

Longitudinal changes in vaginal microbiota composition assessed by gram stain among never sexually active pre- and postmenarcheal adolescents in Rakai, Uganda

STUDY OBJECTIVE

To describe changes in vaginal microbiota and pH over time among never sexually active adolescents at different menarcheal stages.

DESIGN

A cohort of 49 sexually inexperienced Ugandan adolescents provided weekly self-collected vaginal swabs and behavioral/health information for up to two years. Menarcheal stage was classified as: not experiencing menarche during follow-up (premenarcheal, n = 9), achieving menarche during follow-up (perimenarcheal, n = 20), and being postmenarcheal (n = 20) at enrollment. Vaginal microbiota were characterized as morphotypes of large gram-positive rods, small gram-negative or variable rods, and curved gram-negative rods based on Nugent Gram-stain criteria. Baseline measures were compared using nonparametric tests. Mean changes (β) in morphotypes and pH over time were estimated using longitudinal mixed-effects models.

RESULTS

The baseline median (IQR: interquartile range) Nugent score was 8 (7-8) in premenarcheal, 4.5 (1-8) in perimenarcheal, and 1 (0-3) in postmenarcheal girls (P = 0.001). For each respective menarcheal stage, the median (IQR) counts of gram-positive rods were 0 (0-0), 10 (0-30), and 30 (18-30) (P = 0.002) and gram-negative or variable rods were 30 (30-30), 16 (0.5-30), and 0.5 (0-2.5) (P = 0.002) at enrollment. Counts of gram-positive rods increased (β = 0.259, 95% CI: 0.156, 0.362) and gram-negative or variable rods decreased (β = -0.201, 95% CI:-0.298,-0.103) significantly over time in premenarcheal girls, but not in other groups. Vaginal pH declined significantly in peri- and postmenarcheal girls only.

CONCLUSION

Vaginal microbiota composition varied by menarcheal stage at enrollment. Over time, significant changes in vaginal morphotypes occurred in premenarcheal girls, suggesting this may be an important period of transition.

Emergency contraceptive use as a marker of future risky sex, pregnancy, and sexually transmitted infection

OBJECTIVE

The objective of the study was to examine whether emergency contraceptive use predicts future sex at risk for pregnancy, pregnancy, or sexually transmitted infection among young women.

STUDY DESIGN

A secondary analysis of control group participants (n = 718) from a recent trial of advanced provision of emergency contraception was conducted.

RESULTS

We found no association between use of emergency contraception and either pregnancy or infection. Recent use predicted decreased occurrence of subsequent sex at risk for pregnancy among women with a history of sexually transmitted infection (relative risk [RR], 0.39; 95% confidence interval [CI], 0.15-0.97), whereas ever having used predicted increased occurrence among women who either were highly effective method users (RR, 1.45; 95% CI, 1.05-2.01) or had no history of sexually transmitted infection (RR, 1.31; 95% CI, 1.04-1.65).

CONCLUSION

Information about prior emergency contraceptive use was not a useful predictor of subsequent pregnancy, infection, or sex at risk for pregnancy among these young women.

Increased detection of clue cells in smears from cervical intraepithelial lesions with reduced expression of COX-2

The relation between the detection of clue cells in cervical smears of women with CIN and the expression of COX-2 in these lesions were determined. Samples from 228 women, treated due to CIN and who underwent cervical conization, were obtained. Hybrid Capture II and Pap smear samples were collected immediately before performing conization. Pathological diagnoses were 11 (5%) normal cervix, 35 (15%) CIN1, 31 (14%) CIN2, and 151 (66%) CIN3. COX-2 immunoreactivity grading on the pathological specimens was based on the German ImmunoReactive score. In cervical smears, 20 fields (40x) were examined, each of them with a minimum count of 10 epithelial cells. When 20% or more of clue cells were detected the sample was considered positive for clue cells. The prevalence of clue cells was similar across histological strata (P = 0.42). Although the expression of COX-2 did not differ in lesions with varying severities (P = 0.24), there was a negative association between the expression of COX-2 and the presence of clue cells in Pap smear (OR = 0.4; 95% CI = 0.2-0.9): only 12% of women with moderate and strong expression of COX-2 had clue cells in their smears, contrasted to 22% of those with negative and weak expression of COX-2. HPV infection was associated in a borderline manner to the expression of COX-2 (P = 0.04; OR = 2.3 95% CI = 1.0-5.4). The reduced expression of COX-2 in CIN specimens may suggest that clue cells interfere with the inflammatory component of the carcinogenic process that lead to CIN.

The second to fourth digit ratio (2D:4D) in women with and without human papillomavirus and cervical dysplasia

Persistent infection with human papillomavirus (HPV) is associated with a high risk of cervical intraepithelial neoplasia (CIN) and disease progression is influenced by host hormonal factors. The role of fetal exposure to sex steroids has not been explored. The study compared the second to fourth digit ratio (2D:4D), a marker of exposure to fetal androgens, among women with and without HPV and CIN. Data were available from two studies in which HPV, 2D:4D and descriptive variables were assessed cross-sectionally at sexual health clinics. One study (case-control) also assessed cervical smears or biopsies, and some women were retested for persistent HPV. Using these data, 2D:4D was compared among groups defined by cervical smear and HPV result. The cross-sectional data included 90 adolescents and 240 nonadolescents. White women had a significantly higher 2D:4D than other ethnic groups. In the case-control analysis (n = 263), after controlling for ethnicity, women who developed CIN were significantly more likely to have a higher 2D:4D compared with HPV-negative women. A similar, nonsignificant trend was observed among women with a persistent HPV infection.

CONCLUSION

Lower fetal androgen exposure may predispose to persistent HPV and increased risk of CIN.

Flow cytometric quantification of bacteria in vaginal swab samples self-collected by adolescents attending a gynecology clinic

Bacterial vaginosis (BV) is an important risk factor in reproductive health outcomes, such as pre-term birth and sexually transmitted infections including HIV. However, its etiology, diagnosis and treatment remain poorly defined. We evaluated flow cytometry as a tool to quantify total bacterial cells in vaginal specimens self-collected longitudinally by adolescents. BV was diagnosed by Gram-stain (criteria of Hay and Ison). Average flow cytometric counts of bacterial cell-units (BCU) was log(10) 8.04 per gram sample and was found to correlate with sample weight (p<0.0001). BV was frequently observed in this group, with 22 of 32 participants (69%) diagnosed with BV for at least one timepoint. Surprisingly, increased BCU was associated with normal Hay-Ison score (p=0.0003), even when adjusting for sample weight (p=0.02). Since presence and quantity of Lactobacillus defines normal vaginal microbiology (ie. absence of BV), this result indicates a possible bias towards dominance of Lactobacillus cells in measurements of "total" BCU. Increased BCU per gram was associated in multivariate analysis with longer self-reported time since last menstruation (p=0.004) and last sexual intercourse (p=0.007). Sperm was detected in 3 samples provided by those reporting sexual intercourse in the previous 24 h. Light-scattering profiles of bacteria and vaginal cells in samples collected over time from an individual were often identical and distinct from other individuals. To our knowledge, this is the first description of flow cytometry for analysis of commensal bacteria in vaginal specimens. Further development may help to illuminate the complex dynamics of vaginal microbial communities underlying BV.

Risk factors for bacterial vaginosis during pregnancy among African American women

OBJECTIVE

The objective of the study was to examine risk factors for bacterial vaginosis (BV) during pregnancy among African American women.

STUDY DESIGN

As part of a study of preterm birth, African American women residing in Baltimore, MD, were recruited from prenatal care sites. Women enrolled prenatally (between 22 and 28 weeks' gestation) were asked to provide a vaginal smear specimen for ascertainment of BV. Log-binomial analysis was utilized.

RESULTS

Approximately one quarter of the women were identified with BV (110 of 438). After adjusting for several confounders, vaginal douching during pregnancy remained significantly associated with an increased likelihood of BV. In addition, greater frequency of intercourse during the first trimester of pregnancy was significantly associated with an increased likelihood of BV. None of the social or psychosocial factors examined were associated with BV.

CONCLUSION

Douching and sexual activity were associated with an increased risk of BV in the second trimester of pregnancy.

A semi-qualitative study of attitudes to vaccinating adolescents against human papillomavirus without parental consent

Background

The first vaccine to prevent human papillomavirus (HPV) and cervical cancer has been licensed, and in future, vaccination may be routinely offered to 10–14 year old girls. HPV is a sexually transmitted virus and some parents may refuse consent for vaccination. Under-16s in the UK have a right to confidential sexual health care without parental consent. We investigated parents' views on making available HPV vaccination to adolescent minors at sexual health clinics without parental consent.

Methods

This was a semi-qualitative analysis of views of parents of 11–12 year old school children collected as part of a population-based survey of parental attitudes to HPV vaccination in Manchester. Parents were firstly asked if they agreed that a well-informed child should be able to request vaccination at a sexual health clinic without parental consent, and secondly, to provide a reason for this answer. Ethical perspectives on adolescent autonomy provided the framework for descriptive analysis.

Results

307 parents answered the question, and of these, 244 (80%) explained their views. Parents with views consistent with support for adolescent autonomy (n = 99) wanted to encourage responsible behaviour, protect children from ill-informed or bigoted parents, and respected confidentiality and individual rights. In contrast, 97 parents insisted on being involved in decision-making. They emphasised adult responsibility for a child's health and guidance, erosion of parental rights, and respect for cultural and moral values. Other parents (n = 48) wanted clearer legal definitions governing parental rights and responsibilities or hoped for joint decision-making. Parents resistant to adolescent autonomy would be less likely to consent to future HPV vaccination, (67%) than parents supporting this principle (89%; p < 0.001).

Conclusion

In the UK, the principle of adolescent autonomy is recognised and logically should include the right to HPV vaccination, but this may concern parents who would otherwise approve vaccination.

Factors affecting vaginal pH levels among female adolescents attending genitourinary medicine clinics

OBJECTIVES

Vaginal pH is related to hormonal status, and adolescents experience disturbed hormonal patterns following menarche. We assessed hormonal factors and risk of abnormal vaginal pH and bacterial vaginosis (BV) among adolescents attending genitourinary medicine (GUM) clinics.

METHODS

In a cross sectional study adolescents within 5 years of menarche, < or =17 years, or with oligo-amenorrhoea were recruited. Vaginal pH and BV were assessed and among those not using hormonal contraceptives, estrone-3-glucuronide (E3G) and pregnanediol-3alpha-glucuronide (P3G) concentrations were measured.

RESULTS

Among 102 adolescents, 59.8% (61) had a high vaginal pH (>4.5), which was higher than the prevalence of BV, detected in 33% (34). No association was found between presence of sexually transmitted infections (STI) and vaginal pH. In logistic regression, after controlling for BV and condom use, vaginal pH was positively associated with cervical ectopy (OR = 2.5; 95% CI 1.0 to 6.6, p = 0.05) and STI treatment history (OR = 2.5; 95% CI 0.9 to 6.5, p = 0.07), and negatively associated with use of Depo-Provera (OR = 0.1; 95% CI 0.03 to 0.6, p = 0.003) and recent onset (<12 months) of sexual activity (OR = 0.2; 95% CI 0.1 to 0.7, p = 0.004). Among 23 adolescents not using hormonal contraceptives, a high pH occurred more often in abnormal compared to normal menstrual cycles (OR = 10.8; 95% CI 1.4 to 85.4; p = 0.026). E3G concentrations were inversely correlated with vaginal pH in the follicular phase (Spearman: r = 0.51; p = 0.024).

CONCLUSIONS

Ectopy and abnormal menstrual cycles are common features of adolescence. Their presence is associated with increased risk of abnormal pH, and may also predispose to BV.