Relation of Chlamydia trachomatis infections to ectopic pregnancy: A meta-analysis and systematic review

Comparative assessment of Chlamydia trachomatis pathogen prevalence, and the determination of host gyneco-epidemiological and immunological associated risk factors in female infertility

This study investigates the immunopathological responses to Chlamydia trachomatis (Ct) heat shock protein (Ct-Hsp) and their association with infertility. The objective was to explore the prevalence of anti-Ct antibodies and the gyneco-epidemiological risk factors for infertility among women attending a fertility clinic in Zaria, Nigeria, and to analyze the host immune cytokine or Ct-antigen levels in Ct-positive samples for correlation. From December 2022 to January 2024, 215 women (109 infertile and 106 fertile) from Ahmadu Bello University Teaching Hospital participated in this study. Endocervical specimens were tested for Ct-specific IgM and IgG antibodies to identify current and past infections. Additionally, antibodies to Ct-Hsp60, and cytokine levels of IFN-γ and IL-10, were measured using ELISA kits. The overall prevalence of Ct infection was 9.3 %. Past infection, indicated by IgG, was 40 %, while current infection, indicated by IgM, was 25 %. The remaining 35 % of Ct infection were detected by both immunological assay. Among infertile women, primary and secondary infertility prevalence was 41 % and 59 %, respectively. Serum IL-10 levels were significantly higher in Ct-positive infertile women compared to fertile controls. Serum IFN-γ levels were higher in Ct-negative fertile and infertile women than in Ct-positive cases. Serum Ct-Hsp60 levels were significantly higher in Ct-positive fertile women compared to infertile cases. The Th1/Th2 cell ratio was lower in both fertile and infertile women, regardless of Ct status, but fertile controls had a higher Th1/Th2 ratio compared to Ct-positive infertile women. Logistic regression identified significant infertility risk factors: vaginal discharge, age, second marriage, increasing years of childless marriage, and being over 35 years. Protective factors included anti-Ct IgM antibodies, teaching, lower education, and more children. Higher secondary infertility prevalence was linked to family planning history and reactivity to Ct-Hsp60. Ct-positive cases were associated with tubal factor and pelvic inflammatory disease infertility. This study highlights a low overall prevalence of Ct infection but a higher prevalence in women with tubal factor infertility, emphasizing the need for further research on cytokine responses in Ct-associated infertility.

A Landscape View of the Female Genital Tract Microbiome in Healthy Controls and Women With Reproductive Health Conditions Associated With Ectopic Pregnancy

Disruption of the female genital microbiome is associated with several pregnancy complications, including miscarriage, preterm onset of labour, and tubal pregnancy. Ectopic pregnancy is a known cause of maternal morbidity and mortality, but early diagnosis and treatment of ectopic pregnancy remain a challenge. Despite growing established associations between genital microbiome and female reproductive health, few studies have specifically focused on its link with ectopic pregnancy. Therefore, the current review aims to provide a comprehensive account of the female genital microbiome in healthy and fertile women compared to those in ectopic pregnancy and its associated risk factors. The microbial diversity from various sites of the female genital tract was explored for a reliable proxy of female reproductive health in sequencing-based ectopic pregnancy research. Our report confirmed the predominance of Lactobacillus in the vagina and the cervix among healthy women. The relative abundance decreased in the vaginal and cervical microbiome in the disease state. In contrast, there were inconsistent findings on the uterine microbiome across studies. Additionally, we explore a spectrum of opportunities to enhance our understanding of the female genital tract microbiome and reproductive conditions. In conclusion, this study identifies gaps within the field and emphasises the need for visionary solutions in metagenomic tools for the early detection of ectopic pregnancy and other gynaecological diseases.

Associations of Chlamydia trachomatis serology with fertility-related and pregnancy adverse outcomes in women: a systematic review and meta-analysis of observational studies

BACKGROUND

Chlamydia trachomatis (CT) infection has an increased risk for fertility-related and pregnancy adverse outcomes partly due to mechanisms related to a pro-inflammatory response to CT-, or cHSP60-induced delayed hypersensitivity. This study aimed to assess the evidence on the association between CT serology and adverse outcomes.

METHODS

PubMed/Medline, Embase and Web of Science databases were searched for observational studies on the association of CT-specific antibodies (e. g. IgG, IgA, IgM, etc.) with infertility, tubal factor infertility (TFIF), ectopic pregnancy (EP), spontaneous abortion (SA), or preterm labor (PL) that were published from database inception to 31 August 2022. Pooled adjusted odds ratios or relative risks with corresponding 95% confidence intervals were calculated using a random effects model. This study was registered with PROSPERO (CRD42022368366).

FINDINGS

We identified 128 studies that met the inclusion criteria, comprising 87 case-control, 34 cross-sectional and 7 cohort studies, for a total of 167 records involving 128,625 women participants included into the meta-analyses. Based on the adjusted estimates, it was found that CT-specific IgG was significantly associated with TFIF (pooled adjusted OR = 2.09, 95% CI 1.33-3.27, I2 = 63.8%) or EP (pooled adjusted OR = 3.00, 95% CI 1.66-5.40, I2 = 93.0%). Analyses of the unadjusted estimates indicated significant associations between CT-specific IgG and infertility, TFIF, EP or SA (four pooled unadjusted ORs ranging between 1.60 and 5.14, I2 ranging between 40% and 83%); IgA and infertility, TFIF, EP (three pooled unadjusted ORs ranging between 3.64 and 4.91, I2 ranging between 0% and 74%); IgM and TFIF (pooled unadjusted OR = 5.70, 95% CI 1.58-20.56, I2 = 56%); or cHSP60 and TFIF (pooled unadjusted OR = 7.83, 95% CI 5.42-11.31, I2 = 49%).

INTERPRETATION

A broad range of CT-specific antibodies have been studied in association with fertility-related and pregnancy adverse outcomes. However, our study identified a low- or moderate-quality evidence for an association of CT serology with the outcomes. There are substantial research gaps in relation to the clinical implications of CT serological biomarkers.

FUNDING

The work was supported by the Chinese Academy of Medical Sciences Initiative for Innovative Medicine (2016-I2M-3-021).

The environmental risk factors associated with ectopic pregnancy: An umbrella review

INTRODUCTION

Ectopic pregnancy(EP) is the implantation of a fertilized ovum outside of the uterine cavity. The incidence of EP has steadily increased around the world. The present umbrella review evaluated risk factors prior to conception associated with EP based on meta-analyses and systematic reviews.

METHODS

We searched PubMed, Scopus, and Web of Science until June 25, 2021. All meta-analyses that had focused on assessing the risk factors associated with EP were included. We calculated summary effect estimates, 95% CI, heterogeneity I², 95% prediction interval, small-study effects, excess significance biases, and sensitive analysis. The quality of the meta-analyses was evaluated with A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2).

RESULTS

Two risk factors including chlamydia trachomatis (OR: 3.03) and smoking (OR: 1·77) were graded as suggestive evidence (class III). IUD with pregnant control (OR: 10.63) and endometriosis for case-control studies (OR: 2·66) and tubal ligation with pregnant control (OR: 9.3) were graded as risk factors with weak evidence (class IV). Tubal ligation with non-pregnant control was a protective factor (class IV). IUD with non-pregnant control and endometriosis for cohort studies were not as risk factors for EP.

CONCLUSION

Two risk factors including chlamydia trachomatis and smoking were graded as suggestive evidence. IUD with pregnant control and endometriosis for case-control studies and tubal ligation with pregnant control were graded as risk factors with weak evidence. Strong evidence for risk factors of EP was not achieved, indicating the degree of uncertainty and bias, which bring an emergency to conduct further no-bias studies.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO (CRD42021281632).

Association between Chlamydial Infection with Ectopic and Full-Term Pregnancies: A Case-Control Study

Ectopic pregnancies (EPs) are potentially fatal if not recognized early. Evidence of an association with chlamydial infection in South East Asia is lacking. This case-control study aims to (i) compare chlamydial infection in women with EP to women who delivered a full-term pregnancy, (ii) investigate classical factors associated with EP, and (iii) investigate rupture status in EP. Seventy-two women with a confirmed diagnosis of EP and sixty-nine who delivered a full-term pregnancy in a tertiary hospital in Malaysia were recruited from November 2019 to January 2022. Demographic and relevant clinical data and intraoperative findings were documented. Blood samples for testing IgG levels of chlamydia were obtained. Women with EP were more likely to have tested positive for chlamydia than those with a full-term delivery (34.7% vs. 13.0%, AOR = 4.18, 95% CI = 1.67-10.48, p = 0.002). The majority did not have the classic risk factors associated with EP. An amount of 52.8% presented with a ruptured EP, with 84.2% of ruptures occurring after six weeks of gestation. An amount of 44.2% had an estimated blood loss of more than 500 cc, with 20% losing more than 1500 cc of blood. The prevalence of prior chlamydial infection in women with EP is significant enough to necessitate a review of early pregnancy care.

Tubal factor infertility and its impact on reproductive freedom of African American women

In the past, the reproductive freedom of African American women was hindered by forced reproduction and sterilization campaigns. Unfortunately, these involuntary practices have now mostly been replaced by inequality because of disproportionate tubal factor infertility rates within African American communities. Our work aimed to describe the inequities in increased rates of pelvic inflammatory disease and tubal factor infertility as it relates to African American women. In addition, we highlighted the need for improved access to screening and treatment of sexually transmitted infections, access to barrier contraception, and health literacy related to the understanding and prevention of tubal factor infertility in African American women.

Association Between Vaginal Gardnerella and Tubal Pregnancy in Women With Symptomatic Early Pregnancies in China: A Nested Case-Control Study

The early diagnosis and treatment of ectopic pregnancy (EP) remains a major challenge. Despite a known link between vaginal microbiota and female reproductive health, few studies have focused on the association between vaginal microbiota and pregnancy location. This nested case-control study aimed to characterize the vaginal microbiota in tubal pregnancy (TP) among symptomatic women in early pregnancy. Women with symptomatic early pregnancy of unknown location (PUL) were included in this study. 16S rDNA gene sequencing was performed to assess vaginal microbial diversity and relative abundance. Machine learning and multivariate logistic regression were also used to evaluate the association between Gardnerella and TP. The results indicate that the vaginal microbiome in TP was more diverse (Shannon, p < 0.05) and was different in composition to that of women with intrauterine pregnancy (IUP) (weighted Unifrac, R = 0.08, p = 0.01). The genus Gardnerella was significantly enriched in TP. The XGBoost analysis was able to classify Gardnerella-induced TP more reliably (AUC = 0.621). Moreover, after adjusting potential confounders, our results indicate a robust association between Gardnerella and TP (as a continuous variable, adjusted OR: 12.0, 95% CI: 2.1–67.4, p < 0.01; as a categorical variable (≥0.85%), and adjusted OR: 4.2, 95% CI: 2.0–8.8, p < 0.01). In conclusion, we found that higher virginal Gardnerella levels were associated with TP in women with symptomatic early pregnancy.

High prevalence of Chlamydia trachomatis infection among women attending STD and gynecology clinics in Jiangsu province, China: A cross-sectional survey

Epidemics of Chlamydia trachomatis (CT) infection among women are major global public health concerns. This study examined the prevalence of CT infection and associated factors among women attending sexually transmitted disease (STD) and gynecology clinics in Jiangsu province, China.A cross-sectional survey was conducted among women attending STD and gynecology clinics in the province during 2018 to 2019. Socio-demographic and behavioral information were collected through face-to-face questionnaire survey. Cervical swab specimens were collected to test for CT. Chi square tests were used to compare differences in CT prevalence between subgroups of characteristics. Multivariate logistic regression analysis was used to identify factors associated with CT infection.A total of 2664 participants were enrolled. The prevalence of CT infection was 16.6% (95% confidence interval: 15.0%-18.1%). Of those, CT prevalence among participants from STD clinics (19.4%) and South Jiangsu (18.5%) were higher. Female outpatients who were service personnel (adjusted odds ratio [aOR] = 1.667, P = .004) or farmers (aOR = 1.593, P = .039), lived in South Jiangsu (aOR = 1.796, P = .004), and were from STD clinics (aOR = 1.608, P = .022) were more likely to infect CT.Our study showed a high prevalence of CT infection among women attending STD and gynecology clinics in Jiangsu province, China. CT screening, surveillance and treatment promotion should therefore be of top priority on the CT prevention agenda.

Ectopic pregnancies and endometrial microbiota

PURPOSE OF THE REVIEW

In recent years there has been significant progress in the study of endometrial microbiota. This line of investigation has not been free of controversy and discussion. It is a key for clinicians involved to remain updated with the most recent findings in microbiome and its clinical implications to be able to offer patients all possible treatments.

RECENT FINDINGS

The existence of endometrial microbiota now seems undisputed. Current lines of work are centered on dysbiosis and its connection to other pathologies. It is in the field of assisted reproductive technology where this research plays an even more crucial role. In this case, we are focusing our attention toward the study of ectopic pregnancies, searching for similarities in their etiopathogenesis and alterations in the endometrial microbiota.

SUMMARY

Ectopic pregnancy has great repercussions for patients and for the healthcare system. We must continue researching to offer patients techniques and behaviors that can prevent it. The increase in its incidence makes ectopic pregnancy an entity that we must study.

Current Resources for Evidence-Based Practice, May 2020

An extensive review of new resources to support the provision of evidence-based care for women and infants. The current column includes a discussion of a new National Academy of Medicine report on planned place of birth and implications during the SARS-CoV-2 pandemic and commentaries on reviews focused on anorectal sexually transmitted infections and feeding methods following cleft lip repair in infants.