Endometriosis is a chronic inflammatory disease defined as the presence of endometrial tissue outside the uterus, which causes pelvic pain and infertility. This disease should be viewed as a public health problem with a major effect on the quality of life of women as well as being a substantial economic burden. In light of the considerable progress with diagnostic imaging (for example, transvaginal ultrasound and MRI), exploratory laparoscopy should no longer be used to diagnose endometriotic lesions. Instead, diagnosis of endometriosis should be based on a structured process involving the combination of patient interviews, clinical examination and imaging. Notably, a diagnosis of endometriosis often leads to immediate surgery. Therefore, rethinking the diagnosis and management of endometriosis is warranted. Instead of assessing endometriosis on the day of the diagnosis, gynaecologists should consider the patient's 'endometriosis life'. Medical treatment is the first-line therapeutic option for patients with pelvic pain and no desire for immediate pregnancy. In women with infertility, careful consideration should be made regarding whether to provide assisted reproductive technologies prior to performing endometriosis surgery. Modern endometriosis management should be individualized with a patient-centred, multi-modal and interdisciplinary integrated approach.

Rethinking mechanisms, diagnosis and management of endometriosis

Recurrent implantation failure (RIF) refers to cases in which women have had three failed in vitro fertilization (IVF) attempts with good quality embryos. The definition should also take advanced maternal age and embryo stage into consideration. The failure of embryo implantation can be a consequence of uterine, male, or embryo factors, or the specific type of IVF protocol. These cases should be investigated to determine the most likely etiologies of the condition, as this is a complex problem with several variables. There are multiple risk factors for recurrent implantation failure including advanced maternal age, smoking status of both parents, elevated body mass index, and stress levels. Immunological factors such as cytokine levels and presence of specific autoantibodies should be examined, as well as any infectious organisms in the uterus leading to chronic endometritis. Uterine pathologies such as polyps and myomas as well as congenital anatomical anomalies should be ruled out. Sperm analysis, pre-implantation genetic screening and endometrial receptivity should be considered and evaluated, and IVF protocols should be tailored to specific patients or patient populations. Treatment approaches should be directed toward individual patient cases. In addition, we suggest considering a new initial step in approach to patients with RIF, individualized planned activities to activate the brain's reward system in attempt to improve immunological balance in the body.

/pdf/recurrent-implantation-failure-update-overview-on-etiology-3cnsuoxjyw.pdf

Recurrent Implantation Failure-update overview on etiology, diagnosis, treatment and future directions

At implantation, the embryo expresses paternally derived alloantigens and evokes inflammation that can threaten reproductive success. To ensure a robust placenta and sustainable pregnancy, an active state of maternal immune tolerance mediated by CD4+ regulatory T cells (Tregs) is essential. Tregs operate to inhibit effector immunity, contain inflammation, and support maternal vascular adaptations, thereby facilitating trophoblast invasion and placental access to the maternal blood supply. Insufficient Treg numbers or inadequate functional competence are implicated in idiopathic infertility and recurrent miscarriage as well as later-onset pregnancy complications stemming from placental insufficiency, including preeclampsia and fetal growth restriction. In this Review, we summarize the mechanisms acting in the conception environment to drive the Treg response and discuss prospects for targeting the T cell compartment to alleviate immune-based reproductive disorders.

/pdf/regulatory-t-cells-in-embryo-implantation-and-the-immune-2wjjx4c99v.pdf

Regulatory T cells in embryo implantation and the immune response to pregnancy

Background. It is widely assumed that the uterine cavity in non-pregnant women is physiologically sterile, also as a premise to the long-held view that human infants develop in a sterile uterine environment, though likely reflecting under-appraisal of the extent of the human bacterial metacommunity. In an exploratory study, we aimed to investigate the putative presence of a uterine microbiome in a selected series of non-pregnant women through deep sequencing of the V1-2 hypervariable region of the 16S ribosomal RNA (rRNA) gene.

Methods. Nineteen women with various reproductive conditions, including subfertility, scheduled for hysteroscopy and not showing uterine anomalies were recruited. Subjects were highly diverse with regard to demographic and medical history and included nulliparous and parous women. Endometrial tissue and mucus harvesting was performed by use of a transcervical device designed to obtain endometrial biopsy, while avoiding cervicovaginal contamination. Bacteria were targeted by use of a barcoded Illumina MiSeq paired-end sequencing method targeting the 16S rRNA gene V1-2 region, yielding an average of 41,194 reads per sample after quality filtering. Taxonomic annotation was pursued by comparison with sequences available through the Ribosomal Database Project and the NCBI database.

Results. Out of 183 unique 16S rRNA gene amplicon sequences, 15 phylotypes were present in all samples. In some 90% of the women included, community architecture was fairly similar inasmuch B. xylanisolvens, B. thetaiotaomicron, B. fragilis and an undetermined Pelomonas taxon constituted over one third of the endometrial bacterial community. On the singular phylotype level, six women showed predominance of L. crispatus or L. iners in the presence of the Bacteroides core. Two endometrial communities were highly dissimilar, largely lacking the Bacteroides core, one dominated by L. crispatus and another consisting of a highly diverse community, including Prevotella spp., Atopobium vaginae, and Mobiluncus curtisii.

Discussion. Our findings are, albeit not necessarily generalizable, consistent with the presence of a unique microbiota dominated by Bacteroides residing on the endometrium of the human non-pregnant uterus. The transcervical sampling approach may be influenced to an unknown extent by endocervical microbiota, which remain uncharacterised, and therefore warrants further validation. Nonetheless, consistent with our understanding of the human microbiome, the uterine microbiota are likely to have a previously unrecognized role in uterine physiology and human reproduction. Further study is therefore warranted to document community ecology and dynamics of the uterine microbiota, as well as the role of the uterine microbiome in health and disease.

Characterisation of the human uterine microbiome in non-pregnant women through deep sequencing of the V1-2 region of the 16S rRNA gene.

Problem
The aim of this prospective study was to investigate the prevalence of chronic endometritis (CE) in infertile women with a history of repeated implantation failure (RIF) and to determine whether oral antibiotic treatment improves their live birth rate in the following embryo transfer (ET) cycles.

Method of study
Endometrial biopsy samples obtained from infertile women with RIF were subjected to immunohistochemistrical/histopathologic diagnosis of CE. Following antibiotic administration to the RIF/CE group, their histopathologic cure rate, microbial detection rate, and reproductive outcome in the subsequent ET cycles were prospectively studied.

Results
33.7% of infertile women with RIF were diagnosed with CE. Following the first-line doxycycline treatment, the histopathologic cure rate in the subsequent endometrial biopsy was 92.3%. Following the second-line metronidazole/ciprofloxacin treatment, the overall cure rate was 99.1%. The live birth rate in the first ET cycle (P=.031, RR 1.48, 95% CI 1.03-2.12) and cumulative three ET cycles (P=.037, RR 1.39, 95% CI 1.02-1.90) following antibiotic treatment in the cured RIF/CE group (32.8% and 38.8%, respectively) was significantly higher than in the RIF/non-CE group (22.1% and 27.9%, respectively).

Conclusion
Chronic endometritis was found in one-third of infertile women with RIF. The oral antibiotic treatment against CE might be a promising therapeutic option for infertile women with RIF.

Live birth rate following oral antibiotic treatment for chronic endometritis in infertile women with repeated implantation failure.

Recurrent implantation failure refers to failure to achieve a clinical pregnancy after transfer of at least four good-quality embryos in a minimum of three fresh or frozen cycles in a woman under the age of 40years. The failure to implant may be a consequence of embryo or uterine factors. Thorough investigations should be carried out to ascertain whether there is any underlying cause of the condition. Ovarian function should be assessed by measurement of antral follicle count, FSH and anti-Mullerian hormone. Increased sperm DNA fragmentation may be a contributory cause. Various uterine pathology including fibroids, endometrial polyps, congenital anomalies and intrauterine adhesions should be excluded by ultrasonography and hysteroscopy. Hydrosalpinges are a recognized cause of implantation failure and should be excluded by hysterosalpingogram; if necessary, laparoscopy should be performed to confirm or refute the diagnosis. Treatment offered should be evidence based, aimed at improving embryo quality or endometrial receptivity. Gamete donation or surrogacy may be necessary if there is no realistic chance of success with further IVF attempts. Recurrent implantation failure is an important cause of repeated IVF failure. It is estimated that approximately 10% of women seeking IVF treatment will experience this particular problem. It is a distressing condition for patients and frustrating for clinicians and scientists. In this review, we have discussed the definition and management of the possible underlying causes of recurrent implantation failure.

https://www.rbmojournal.com/article/S1472-6483(13)00475-6/pdf

K. Ong

Papers

Recurrent implantation failure: definition and management