Efficacy and safety of Zi Gui Nv Zhen® capsules used in TCM for fertility preservation in patients with diminished ovarian reserve.

OBJECTIVE: To evaluate for the first time whether Zi Gui Nv Zhen® capsules (ZGNZC), until now used in traditional Chinese medicine (TCM) for menopausal complaints, can increase the fertility of Chinese women with diminished ovarian reserve (DOR). METHODS: Prospective, randomized, open-labeled 3-monthly study; 109 DOR patients (aged 20-40 years) receiving either ZGNZC (experimental group, n = 75) or not (control group, n = 34). Main outcomes: markers for ovarian function, thickness/type of the endometrium during ovulation, and pregnancy rate. Between-group analysis (A) comparing experimental vs. control group and within-group analysis (B) comparing data at baseline and after study in each of both groups. RESULTS: (A) Between-group-analysis: patients with ZGNZC had a higher endometrium thickness (0.75 vs. 0.62; p<.05) and higher anti-Müllerian hormone (AMH, 0.50 vs. 0.40; p<.05) than control group. Pregnancy rates were higher in the experimental than the control group (26.7% vs. 14.7%; n.s.). (B) Within-group-analysis: ZGNZC decreased levels of follicle-stimulating hormone (FSH, 11.42 vs. 8.69), increased estradiol-levels (E2, 56.09 vs. 73.36), and type A endometrium rates (5.3% vs. 39.7%) (all p< .05) and increased antral follicle count (AFC, 2 vs. 3). All hepato-renal biomarkers remained within the norm. The tolerability was good. There were no adverse events. CONCLUSIONS: In women with DOR who wish to conceive, three months' application of ZGNZC can improve ovarian function and oocyte quality by adjusting the neuroendocrine system, can improve endometrial properties and proliferation, necessary for a healthy pregnancy, and increased the clinical pregnancy rate in our prospective randomized observational study.

Vaginal health, endometrial thickness and changes in bone markers in postmenopausal women after 6 months of treatment with ospemifene in real clinical practice.

OBJECTIVE: To assess vaginal health, endometrial thickness, and changes in bone markers in postmenopausal women with vulvovaginal atrophy (VVA) treated with 60 mg/day of ospemifene under routine clinical practice. METHODS: The AYSEX study is a Spanish observational and prospective study performed in one center in which 5 gynecologists recruited postmenopausal women with VVA in routine clinical practice treated continuously with ospemifene 60 mg/day for 12 months as an appropriate therapeutic option. This article refers to the 3- and 6-months analysis. Vaginal health was assessed by pH and using Vaginal Health Index (VHI) at baseline and 3 months later. Endometrial thickness, measured by vaginal ultrasonography, and bone resorption marker (CTx) were assessed at baseline and 6 months later. RESULTS: A total of 100 postmenopausal women cytologically and clinically diagnosed with VVA were included in the study. After 3 months of treatment with ospemifene, pH improved from 6.1 to 4.5 (p < .0001), and VHI improved from 10 to 19 points (p < .0001). The percentage of patients with VVA according to VHI decreased from 100% to 5.2% (p < .0001). After 6 months, mean CTx levels decreased from 0.42 pg/ml at baseline to 0.37 pg/ml 6 months later (p = .0018), and mean endometrial thickness changed from 2.24 to 2.15 mm (p = .6066). CONCLUSIONS: Up to date, this is the only prospective and observational study with ospemifene in routine clinical practice conditions and confirms the results previously reported from randomized controlled clinical trials, improving VVA, not increasing endometrial thickness, and decreasing CTx levels by exerting an anti-resorptive function.

Multifactor Prediction of Embryo Transfer Outcomes Based on a Machine Learning Algorithm.

In vitro fertilization-embryo transfer (IVF-ET) technology make it possible for infertile couples to conceive a baby successfully. Nevertheless, IVF-ET does not guarantee success. Frozen embryo transfer (FET) is an important supplement to IVF-ET. Many factors are correlated with the outcome of FET which is unpredictable. Machine learning is a field of study that predict various outcomes by defining data attributes and using relevant data and calculation algorithms. Machine learning algorithm has been widely used in clinical research. The present study focuses on making predictions of early pregnancy outcomes in FET through clinical characters, including age, body mass index (BMI), endometrial thickness (EMT) on the day of progesterone treatment, good-quality embryo rate (GQR), and type of infertility (primary or secondary), serum estradiol level (E2) on the day of embryo transfer, and serum progesterone level (P) on the day of embryo transfer. We applied four representative machine learning algorithms, including logistic regression (LR), conditional inference tree, random forest (RF) and support vector machine (SVM) to build prediction models and identify the predictive factors. We found no significant difference among the models in the sensitivity, specificity, positive predictive rate, negative predictive rate or accuracy in predicting the pregnancy outcome of FET. For example, the positive/negative predictive rate of the SVM (gamma = 1, cost = 100, 10-fold cross validation) is 0.56 and 0.55. This approach could provide a reference for couples considering FET. The prediction accuracy of the present study is limited, which suggests that there may be some other more effective predictors to be developed in future work.

Relationship between the Metabolic Associated Fatty Liver Disease and Endometrial Thickness in Postmenopausal Women: A Cross-sectional Study in China.

Objectives: To determine the relationship between the endometrial thickness (ET) and metabolic associated fatty liver disease (MAFLD) in the postmenopausal women who have a comprehensive health examination. Methods: This was a population-based, retrospective observational study of the prevalence of MAFLD in 8594 postmenopausal women with different ET in the Quality Control Center of Health Examination in Chongqing, China. Binary and multivariable logistic regression analyses were used to obtain odds ratios and 95% confidence intervals for patients of different ET with MAFLD after adjusting for age. Results: The incidences of MAFLD were 28.6% (1352), 30.3% (1058), 34.9% (133) in postmenopausal women with ET of < 3 mm, 3 mm ≤ & < 5 mm, and ≥ 5 mm, respectively. Compared with a baseline ET of less than 5.0 mm, the risk of MAFLD in patients with ET of ≥5.0 mm is higher (OR=1.291, 95% CI: 1.041-1.603, P<0.05). After adjustment for age, a statistically significant positive correlation was still observed. The increased prevalence of MAFLD in patients with ET of 3 mm ≤ &<5 mm (OR=1.110, 95% CI: 1.008-1.223) and ≥5 mm (OR=1.383, 95% CI: 1.109-1.724) achieved statistical significance, respectively. In addition, multiple logistic analyses controlling for age also confirmed the finding of positive correlation among body mass index (BMI) and ET. Conclusion: Our results suggest that there is a positive correlation between MAFLD and ET in postmenopausal women. In addition, increased BMI is also associated with an increased risk of thickened endometrium.

MRI of the endometrium - from normal appearances to rare pathology.

MRI was recently included as a standard pre-operative diagnostic tool for patients with endometrial cancer. MR findings allow a better risk assessment and ultimately guides the surgical planning. Therefore, it is vital that the radiological interpretation is as accurate as possible. This requires essential knowledge regarding the appropriate MRI protocol, as well as different appearances of the endometrium, ranging from normal peri- and post-menopausal changes, benign findings (e.g. endometrial hyperplasia, polyp, changes due to exogenous hormones) to common and rare endometrium-related malignancies. Furthermore, this review will emphasize the role of MRI in staging endometrial cancer patients and highlight pitfalls that could result in the underestimation or overestimation of the disease extent.

Use of Intra-uterine Injection of Platelet-rich Plasma (PRP) for Endometrial Receptivity and Thickness: a Literature Review of the Mechanisms of Action.

Endometrial receptivity and thickness play an important role in achieving a pregnancy. Intrauterine autologous platelet-rich plasma (PRP) infusion has been used in infertile women with recurrent implantation failure (RIF) and thin endometrial lining thickness (EMT). Literature search was performed in PubMed for studies including in vitro, animal, and human studies as well as in abstracts presented at national conferences. Animal studies demonstrated a decrease in the expression of inflammatory markers and fibrosis, and increased endometrial proliferation rate, increased expression of proliferative genes, and increased pregnancy rates. The in vitro studies showed that PRP was associated with increased stromal and mesenchymal cell proliferation, increased expression of regenerative enzymes, and enhancement in cell migration. In infertile women undergoing assisted reproductive technology, one randomized clinical trial showed that PRP intrauterine infusion improved EMT, implantation rate, and clinical pregnancy rate (CPR) in patients with thin EMT, while 3 other trials involving subjects with RIF showed conflicting results related to CPR. Case series and cohort studies showed conflicting results pertaining to CPR. Data to date suggest that PRP may be beneficial in improving endometrial thickness and endometrial receptivity. However, further large prospective and high-quality trials are needed to assert its effect and to identify the population of patients that would benefit the most.

The predictive value of serial serum estradiol and serial endometrial volume on endometrial receptivity on assisted reproductive technology cycles.

BACKGROUND: Diagnosis of endometrial receptivity is still unclear and conflicting. Despite advances in embryo development during assisted reproductive technologies (ART) cycles, the intricate process of implantation is still matter for debate and research. MATERIALS AND METHODS: Prospective case control of 169 subjects during ovarian controlled stimulation for ART. Endometrial receptivity assessment to predict clinical pregnancy with serial continuous biochemical (serum estradiol) and biophysical (endometrial volume and adjusted endometrial volume) parameters were used. Both parameters were compared between negative and positive outcome in terms of clinical pregnancy. RESULTS: No statistical difference was noted between the two groups in terms of demographics and ART procedures and scores. Serum estradiol was significantly higher in the positive group from day 8 after ovarian controlled stimulation. Endometrial volume and adjusted endometrial volume were significantly higher in the positive group as soon as day 6 of ovarian controlled stimulation. CONCLUSIONS: Continuous serum estradiol and 3D endometrial volume and adjusted endometrial volumes may reflect endometrial changes during ART procedures and provide a useful real time tool for clinicians in predicting endometrial receptivity.

In vitro models of the human endometrium: evolution and application for women's health.

The endometrium is the inner lining of the uterus that undergoes complex regeneration and differentiation during the human menstrual cycle. The process of endometrial shedding, regeneration, and differentiation is driven by ovarian steroid hormones and prepares the endometrium and intrauterine environment for embryo implantation and pregnancy establishment. Endometrial glands and their secretions are essential for pregnancy establishment, and cross talk between the glandular epithelium and stromal cells appears vital for decidualization and placental development. Despite being crucial, the biology of the human endometrium during pregnancy establishment and most of pregnancy is incomplete, given the ethical and practical limitations of obtaining and studying endometrium from pregnant women. As such, in vitro models of the human endometrium are required to fill significant gaps in understanding endometrial biology. This review is focused on the evolution and development of in vitro three-dimensional models of the human endometrium and provides insight into the challenges and promises of those models to improve women's reproductive health.

Endometrial thickness in the evaluation of clinical response to medical treatment for deep infiltrating endometriosis: a retrospective study.

PURPOSE: Deep infiltrating endometriosis (DIE) is associated with severe pelvic pain and functional impairment of bowel, urinary, and sexual functions. Though hormone therapy with progestins, either as single agents or combined with estrogens, is effective in managing symptoms, some patients may experience a suboptimal response. Endometrial thickness assessed by transvaginal ultrasound examination, reflecting the overall estrogen stimulation, may correlate with the clinical response to hormonal treatments. METHODS: A retrospective study was carried out on 61 women with DIE affecting the bowel or the recto-vaginal septum, undergoing hormone treatment. The symptoms of patients were evaluated at the baseline and after 12 months of therapy, calculating a global Visual Analogue Scale score (gVAS) encompassing dysmenorrhea, dyspareunia, chronic pelvic pain, dyschezia, abdominal pain and dysuria. Patients were divided into two subgroups using, as a calculated cut-off value, the mean endometrial thickness in our population at 12 months. The change in gVAS score during the 12 months of treatment was then compared between the two groups. RESULTS: Women with a thinner endometrium (< 3.3 mm) showed a better response to treatment in terms of symptoms control as compared to patients with a thicker endometrium (mean gVAS score reduction 9.2 ± 1.3 vs. 5.2 ± 1.3, p = 0.036). The correlation between endometrial thickness and symptomatic response was also confirmed (p = 0.041) on multivariate linear regression analysis including as covariates age, size of lesions of DIE, presence of uterine adenomyosis, ovarian endometriosis and type of medical treatment. CONCLUSION: Endometrial thickness on ultrasound transvaginal examination is correlated with better response rates to hormone therapy in terms of symptoms control. A thinner endometrium, probably resulting from a more efficient suppression of estrogen stimulation, is associated with improved symptoms. These results may aid clinicians in monitoring and tailoring hormonal treatments during follow-up of women with symptomatic DIE.

The Effects of Endometrial Thickness on Pregnancy Outcomes of Fresh IVF/ICSI Embryo Transfer Cycles: An Analysis of Over 40,000 Cycles Among Five Reproductive Centers in China.

Objective: To investigate the effects of endometrial thickness (EMT) on pregnancy outcomes on hCG trigger day in fresh in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) cycles. Methods: A total of 42,132 fresh cycles between 1 January 2013 and 31 December 2019 were included in this retrospective cohort study. Data were collected from five reproductive centers of large academic or university hospitals in China. All patients were divided into different groups according to their endometrial thickness on hCG trigger day. Multivariate regression analysis, curve fitting and threshold effect analysis were performed. Results: After adjusting for age, body mass index, infertility type, number of embryos transferred, number of retrieved oocytes and COS (controlled ovarian stimulation) protocols, significant associations were found between endometrial thickness and clinical pregnancy rate (adjusted odds ratio [aOR]: 1.05; 95% confidence interval [CI]: 1.06-1.08, P < 0.0001), live birth rate (aOR: 1.04; 95% CI: 1.03-1.05, P < 0.0001) as well as miscarriage rate(aOR: 0.96; 95% CI: 0.94 - 0.98, P < 0.0001). When the endometrial thickness was less than 12mm, the clinical pregnancy rate and live birth rate were increased significantly by 10% and 9%(OR:1.10; 95%CI: 1.08-1.12, OR:1.09; 95%CI: 1.07-1.11), respectively, along with the increase of each millimeter increment of endometrial thickness. However, when the EMT ranged from 12-15 mm, were stable at the ideal level, that were not significantly associated with EMT growth. Additionally, clinical pregnancy rate and live birth rate were slightly reduced by 6% and 4% when EMT was ≥15mm. Meanwhile, the miscarriage rate was significantly declined by 8% (OR:0.92; 95%CI: 0.90-0.95)with each millimeter increment of EMT. And when EMT was thicker than 12mm, the miscarriage rate didn't change any more significantly. Conclusions: Endometrial thickness exhibits a curvilinear relationship with pregnancy outcomes in fresh embryo transfer cycles. Clinical pregnancy rate, live birth rate and miscarriage rate may achieve their optimal level when EMT ≥ 12 mm, but some adverse pregnancy outcomes would be observed when EMT ≥15 mm especially for clinical pregnancy.

The effect of endometrial thickness and pattern on the success of frozen embryo transfer cycles and gestational age accuracy.

OBJECTIVE: To evaluate the relationship between endometrial thickness measured before embryo transfer, and pregnancy outcomes in frozen-thawed embryo transfer (FET). METHODS: We retrospectively analyzed outcomes of all consecutive FET cycles, from January 2012 to August 2018. Based on ROC analysis for endometrial thickness, we found 8 mm was a reliable cutoff point to predict pregnancy prior to embryo transfer. Accordingly, the cycles were divided into Group A: cycles with endometrial thickness ≤ 8 mm and Group B: > 8 mm. RESULTS: Group A included 485 FET cycles and group B included 626 cycles. Compared with group A, Group B had significantly higher chemical and clinical pregnancy rates (30.3 vs. 24.6%; p = .046, and 24.0 vs. 18.6%; p = .036), respectively. In multivariate analysis, endometrial thickness and the protocols used were the only parameters influencing the chance to achieve pregnancy, with odds ratio 1.54 (95%CI 1.07-2.22, p = .019) for the endometrium and odds ratio 1.95 (95%CI 1.31-2.9; p = .001) to the protocol used. Endometrial thickness might predict crown-rump length (CRL) discordancy with odds ratio 4.61 (p = .001; 95% CI 1.42-14.92). Compared with group B, Group A had more cases of overt discordancy (13.3 vs. 4%; p = .016). CONCLUSIONS: For patients undergoing FET cycles, endometrial thickness and treatment protocol may predict the chemical and clinical pregnancy rates, as well as CRL discordancy. SUMMARY: Endometrial thickness and preparation improved pregnancy rate in FET cycles and significantly greater crown-rump length discordancy was observed with thinner endometria.

Value of endometrial thickness change after human chorionic gonadotrophin administration in predicting pregnancy outcome following fresh transfer in vitro fertilization cycles.

PURPOSE: To study whether the change of endometrial thickness (EMT) between the day of human chorionic gonadotrophin (hCG) administration and the day of embryo transfer has any impact on pregnancy outcome in fresh in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles. METHODS: This single-center retrospective cohort study included 2620 patients undergoing their first consecutive autologous IVF/ICSI cycles from January 2003 to December 2012. Patients were categorized into three groups based on the percentage change of post-hCG EMT: > 10% decrease, ± 10% plateau and > 10% increase. The primary outcome was live birth rate. RESULTS: Live birth rates were similar in the EMT decrease, plateau and increase groups (27.4% [174/635], 29.7% [300/1010] and 27.6% [269/975]; P = 0.649). Compared with the plateau group, both EMT decrease (crude odds ratio [cOR] 0.89, 95% confidence interval [CI] 0.72-1.11) and increase (cOR 0.90, 95% CI 0.74-1.10) on the day of transfer did not affect the likelihood of live birth. The non-significant association was maintained after controlling for major confounding factors, with the adjusted OR being 0.92 (95% CI 0.73-1.16) and 0.92 (95% CI 0.75-1.13) for the decrease and increase groups, respectively. CONCLUSION: EMT change after hCG administration did not provide significant prognostic information for pregnancy outcome in fresh IVF/ICSI cycles. This finding should offer reassuring information for patients with decreased EMT on the day of embryo transfer while questioning the necessity of EMT re-measurement prior to transfer as a routine practice.

Expression of monocyte chemotactic protein 2 and tumor necrosis factor alpha in human normal endometrium and endometriotic tissues.

Endometriosis is a gynocological disease characterized by the presence of the endometrial glands and stroma outside the uterine cavity. This disease affects % 6-10 of women with reproductive age and it causes serious problems such as pelvic pain, dysmenorrhea and infertility. Although endometriosis is one of the most investigated disease of gynecology, its pathogenesis is not clear completely. In recent years, many studies revealed the inflammatory nature of endometriosis. Many of the immune cells and their secretory products cytokines and chemokines has been detected in body fluids of women with endometriosis. Cytokines are protein or glycoprotein in structures and hormon-like molecules that act generally in a paracrine fashion to regulate immun responses. They involved in chemotaxis, cell proliferation, cell activation, motility, adhesion and morphogenesis. Tumor necrosis factor alpha (TNF-α) is a proinflammatory cytokine secreted by the macrophages, monocytes, neutrophiles, T cells and natural killer cells. It stimulates increase in the level of the chemokines in body fluids. Monocyte chemotactic protein 2 (MCP-2) is a chemokine act to recruit and activate monocytes into sites of inflammation area. The aim of this study to investigate the ultrastructural properties and whether the expression and localization of TNF-α and MCP-2 in the eutopic endometrium (normal endometrium of women with endometriosis) and endometritic tissues of women with endometriosis. Eutopic endometrial and endometriotic tissue samples were obtained from women with endometriosis between 20-41 y and normal endometrial tissues were collected from 5 women without endometriosis as a control group. Tissues were processed for light and electron microscopy and examined. The epithelial cells of endometriotic tissues were revealed strongly cytoplasmic TNF-α and MCP-2 immunreactivities. Eutopic endometrial tissues were also stained prominently for both TNF-α and MCP-2. Furthermore, a significant increase in stromal macrophages were observed in endometriotic tissues. Moreover, the ultrastructural observations on the normal and endometriotic tissues were exhibited microvilli-rich cells and ciliated cells. These findings suggest that TNF-α and MCP-2 may be involved in normal endometrial biology and in the pathogenesis of endometriosis.

Continuous endometrial volumetric analysis for endometrial receptivity assessment on assisted reproductive technology cycles.

BACKGROUND: Human implantation is a complex process requiring synchrony between a healthy embryo and a functionally competent or receptive endometrium. In order to assess endometrial receptivity in Assisted Reproductive Technology (ART) cycles serial evaluation of endometrial volumetric analysis may have a predictive value on a positive outcome. METHODS: Serial 3D transvaginal ultrasound performed in women on ART cycle to evaluate embryo implantation predictors. Prospective case control study of 169 subjects were assessed. Endometrial pattern, thickness, volume and adjusted endometrial volume (ratio between endometrial volume and uterine volume) was performed to all subjects on a continuous process from baseline, during controlled ovarian stimulation, trigger day with human chorionic gonadotropin hormone (hCG) and at embryo transfer day. RESULTS: Demographics and ART procedures and scores, was similar between the two groups. Endometrial morphology also showed no difference between the two groups. Endometrial volume and adjusted endometrial volume was significantly higher in the positive group as soon as day 6 of ovarian controlled stimulation. CONCLUSIONS: Serial 3D endometrial volume and adjusted endometrial volumes provides a predicting clinical tool enhancing elective embryo transfers in fresh ART cycle. Thus providing a non-invasive continuous technique for endometrial receptivity assessment that reflects endometrial changes during ART procedures.

The effect of endometrial thickness on pregnancy outcomes of frozen-thawed embryo transfer cycles which underwent hormone replacement therapy.

OBJECTIVE: To investigate the impact of endometrial thickness on the embryo transfer(ET) day on the clinical pregnancy outcomes of frozen-thawed embryo transfer cycles which have undergone hormone replacement therapy(HRT-FET). METHODS: A total of 10,165 HRT-FET cycles performed between January 2013 to December 2017 in the Reproductive Medicine Center of Henan Provincial People's Hospital were studied retrospectively. All patients were grouped according to their endometrial thickness on the ET day (each group having an increment of 1mm between two neighboring groups). Multivariate regression analysis, curve fitting and threshold effect analysis were performed on all data. RESULTS: After adjusting for the age, duration of infertility, body mass index(BMI), infertility type and number and type of embryos transferred, a significant correlation was observed to be between the endometrial thickness and implantation rates (aOR: 1.08; 95% CI: 1.06-1.10, p < 0.0001), clinical pregnancy rate(aOR: 1.10; 95% CI: 1.07-1.14, p < 0.0001)and live birth rate (aOR: 1.09; 95% CI: 1.06-1.12, p < 0.0001). The numerical value of the cut-off point for the endometrial thickness was 8.7 mm. When the endometrial thickness was less than 8.7 mm, with each additional 1 mm of endometrial thickness, the implantation rate increased by 32%, the clinical pregnancy rate increased by 36%, and the live birth rate increased by 45%. CONCLUSIONS: In the HRT-FET cycles, the optimal live birth rate would be obtained when the endometrial thickness remains within the range of 8.7-14.5 mm. If the endometrium is too thin or too thick, the live birth rate will be reduced.

A review of in vivo and in vitro studies of the mare endometrium.

The inner layer of the uterus, the endometrium, is responsible and necessary for many reproductive functions. Normal reproductive cyclicity, maternal recognition of pregnancy, maternal interaction with the embryo, and interaction of the reproductive tract with pathogens are dependent on the endometrium. Although most studies have been conducted in vivo using live animals, recent advances in in vitro approaches could facilitate future research in a laboratory setting with minimal effect on animals. Many reproductive studies have been performed in vivo and in vitro in equids, but new in vitro methods to study the endometrium of mares remain unexplored. In this review, there is a description of the normal anatomy and physiology of the mare endometrium in vivo, in vitro endometrial cell culture techniques that have been previously described for the mare, and opportunities for future reproductive research using in vitro methods.

Clinical value of histologic endometrial dating for personalized frozen-thawed embryo transfer in patients with repeated implantation failure in natural cycles.

BACKGROUND: Displacement of the window of implantation (WOI) has been proposed as an important factor contributing to repeated implantation failure (RIF). However, the use of histologic endometrial dating as a diagnostic tool of endometrial receptivity has been questioned. METHODS: This study is a prospective intervention trial that enrolled 205 infertile patients from July 2017 to December 2017. Endometrial biopsies from 50 patients with good prognoses were conducted on day 3 (n = 6), 5 (n = 6), 7 (n = 26), 9 (n = 6), or 11 (n = 6) post-ovulation (PO + 3/5/7/9/11) of the previous natural cycle before their conventional frozen-thawed embryo transfer (FET) cycle. We conducted endometrial biopsies for 155 RIF patients on day PO + 7. RESULTS: The verification of the Noyes criteria for endometrial dating was conducted at different times (PO + 3/+ 5/+ 7/+ 9/+ 11) on 41 patients with good prognoses who achieved an ongoing pregnancy in their first conventional FET cycle after endometrial biopsy. The agreement between two pathologists determining endometrial biopsy dating results in infertile patients was determined to be acceptable (weighted kappa = 0.672, P < 0.001). The rate of out-of-phase dating on day PO + 7 was significantly higher in RIF patients than in good- prognosis patients (31.6% vs. 3.8%, P = 0.003). pFET was performed in 47 RIF patients diagnosed to be out of phase, and the cumulative live-birth rate was 61.7%. CONCLUSIONS: Histologic endometrial dating of RIF patients in natural cycles may be a biomarker for a receptive endometrium in diagnosing WOI displacement. TRIAL REGISTRATION: NCT03312309 Registered 17 October 2017. NCT03222830 Registered 19 July 2017.

Absence of lymphatic vessels in term placenta.

BACKGROUND: There has been debate about the existence of lymphatic vessels in placenta. Lymphatic endothelial cell (LEC) markers such as LYVE-1 and podoplanin/D2-40 have been found, although PROX1 has not been detected. The most reliable marker for LECs is the double staining for CD31 and PROX1, which has not been performed yet. METHODS: We studied three term placentas and dissected them into three areas: i.) basal plate area, ii.) intermediate area, and iii.) chorionic plate area. We used immunofluorescence single and double staining with antibodies against CD31, PROX1, LYVE-1, VEGFR-3, D2-40/PDPN, CD34, CCBE-1, and vimentin, as well as nested PCR, qPCR, Western blot and transmission electron microscopy (TEM). RESULTS: At TEM level we observed structures that have previously mistakenly been interpreted as lymphatics, however, we did not find any CD31/PROX1 double-positive cells in placenta. Absence of PROX1 was also noted by nested PCR, qPCR and Western blot. Also, LEC marker VEGFR-3 was expressed only in a small number of scattered leukocytes but was absent from vessels. The LEC marker D2-40/PDPN was expressed in most stromal cells, and the LEC marker LYVE-1 was found in a considerable number of stromal cells, but not in endothelial cells, which were positive for CD31, CD34, CCBE-1 and vimentin. Additionally, vimentin was found in stromal cells. CONCLUSIONS: Our studies clearly show absence of lymphatics in term placenta. We also show that the functional area of the mother's endometrium is not penetrated by lymphatics in term pregnancy.

Baseline Endometrial Thickness or Endometrial Thickness Change in Response to Estrogen Is Not Predictive of Frozen Embryo Transfer Success in Medicated Cycles.

There is some consensus that endometrial thickness (EMT) needs to be at least 7 mm on day of embryo transfer. However, the predictive role of baseline EMT and EMT change in response to estrogen is largely unknown. The objective of this study was to evaluate the role of endometrial thickness in frozen embryo transfer (FET) cycles. We analyzed the association of baseline endometrial thickness (EMTb-Day 3 of cycle) and endometrial thickness change (EMTΔ-from baseline to start of progesterone supplementation) with FET success in 121 cycles. We also investigated whether baseline estradiol levels and body mass index (BMI) are associated with EMTb. No difference was observed in EMTb and EMTΔ in cycles resulting in clinical pregnancy compared to unsuccessful transfers (5.1 ± 2.2 mm vs 5.0 ± 1.9 mm; p = 0.92, and 4.7 ± 2.4 mm vs. 4.4 ± 2.4 mm; p = 0.56). When 7 mm cut-off was used, endometrial thickness on the day of start of progesterone supplementation (EMTp) was also not different between groups (9.8 ± 2.9 mm vs. 9.4 ± 2.5 mm; p = 0.50). Multivariable logistic regression models did not demonstrate any predictive value of EMTb, EMTp, or EMTΔ in predicting success of FET cycles (p = 0.92, p = 0.80, and p = 0.84, respectively). There was no significant correlation between EMTb and baseline estradiol levels (r = -0.001; p = 0.985). BMI showed statistically significant weak positive linear relationship with EMTb (r = +0.29; p = 0.002). Our study did not demonstrate any significant relationship between baseline endometrial thickness or endometrial thickness change and clinical pregnancy rates in frozen embryo transfer cycles. Significant positive linear relationship of BMI with baseline endometrial thickness, despite no correlation between baseline estradiol and EMTb, points to the role of possible other mechanism affecting EMT besides estradiol in obese patients.