Uncovering the role of TET2-mediated ENPEP activation in trophoblast cell fate determination.

Early trophoblast differentiation is crucial for embryo implantation, placentation and fetal development. Dynamic changes in DNA methylation occur during preimplantation development and are critical for cell fate determination. However, the underlying regulatory mechanism remains unclear. Recently, we derived morula-like expanded potential stem cells from human preimplantation embryos (hEPSC-em), providing a valuable tool for studying early trophoblast differentiation. Data analysis on published datasets showed differential expressions of DNA methylation enzymes during early trophoblast differentiation in human embryos and hEPSC-em derived trophoblastic spheroids. We demonstrated downregulation of DNA methyltransferase 3 members (DNMT3s) and upregulation of ten-eleven translocation methylcytosine dioxygenases (TETs) during trophoblast differentiation. While DNMT inhibitor promoted trophoblast differentiation, TET inhibitor hindered the process and reduced implantation potential of trophoblastic spheroids. Further integrative analysis identified that glutamyl aminopeptidase (ENPEP), a trophectoderm progenitor marker, was hypomethylated and highly expressed in trophoblast lineages. Concordantly, progressive loss of DNA methylation in ENPEP promoter and increased ENPEP expression were detected in trophoblast differentiation. Knockout of ENPEP in hEPSC-em compromised trophoblast differentiation potency, reduced adhesion and invasion of trophoblastic spheroids, and impeded trophoblastic stem cell (TSC) derivation. Importantly, TET2 was involved in the loss of DNA methylation and activation of ENPEP expression during trophoblast differentiation. TET2-null hEPSC-em failed to produce TSC properly. Collectively, our results illustrated the crucial roles of ENPEP and TET2 in trophoblast fate commitments and the unprecedented TET2-mediated loss of DNA methylation in ENPEP promoter.

Myd88 Signaling Is Involved in the Inflammatory Response in LPS-Induced Mouse Epididymitis and Bone-Marrow-Derived Dendritic Cells.

Epididymitis is an epididymal inflammation that may lead to male infertility. Dendritic cells (DCs) and myeloid differentiation primary response gene 88 (Myd88) were associated with epididymitis in rodents. However, the functions of Myd88 on epididymal DCs remain unclear. This study investigated the role of Myd88 in DCs for epididymitis. The Myd88 signaling pathway, phenotypes of DC subsets, and cytokines were investigated in lipopolysaccharide (LPS)-induced epididymitis in mice. CRISPR-Cas9 was used to knockout Myd88 in bone-marrow-derived dendritic cells (BMDCs) and immortalized mouse epididymal (DC2) cell line. In the vivo experiments, levels of the proinflammatory cytokines IL-1α, IL-6, IL-17A, TNF-α, IL-1ß, MCP-1, and GM-CSF, mRNA for MyD88 related genes, and the percentages of monocyte-derived DCs (Mo-DCs) were significantly elevated in mice with epididymitis. In the vitro experiments, LPS significantly promoted the apoptosis of BMDCs. In addition, the concentration of inflammatory cytokines in BMDCs and DC2s were increased in the LPS group, while decreasing after the knockout of Myd88. These findings indicate that Myd88 on DCs is involved in the inflammation of epididymitis in mice, which may be a potential target for better strategies regarding the treatment of immunological male infertility.

The involvement of let-7 in hCG-induced progesterone synthesis via regulating p27Kip1 and p21Cip1 expression.

Progesterone is essential in females to maintain a regular menstrual cycle and pregnancy. The luteinizing hormone (LH) surge induces the luteinization of granulosa cells and thecal cells to form the corpus luteum, which is responsible for progesterone synthesis. However, the specific mechanism of how hCG, the analog of LH, regulates progesterone synthesis has yet to be fully discovered. In this study, we found that progesterone level was increased in adult wild-type pregnant mice 2 and 7 days post-coitum, along with a decrease in let-7 expression compared with the estrus stage. Besides, the let-7 expression was negatively correlated with progesterone level in post-delivery day 23 wild-type female mice after being injected with PMSG and hCG. Then, using let-7 transgenic mice and a human granulosa cell line, we found that overexpression of let-7 antagonized progesterone level via targeting p27Kip1 and p21Cip1 and steroidogenic acute regulatory protein (StAR) expression, which is a rate-limiting enzyme in progesterone synthesis. Furthermore, hCG suppressed let-7 expression by stimulating the MAPK pathway. This study elucidated the role of microRNA let-7 in regulating hCG-induced progesterone production and provided new insights into its role in clinical application.

Follicular helper T lymphocytes in the endometria of patients with reproductive failure: Association with pregnancy outcomes and inflammatory status of the endometria.

PROBLEM: The phenotypes and functions of B and CD4+ T-helper cell subsets during chronic inflammation of the endometria remain largely unexplored. This study aimed to investigate the characteristics and functions of follicular helper T (Tfh) cells to understand the pathological mechanisms of chronic endometritis (CE). METHOD OF STUDY: Eighty patients who underwent hysteroscopic and histopathological examinations for CE were divided into three groups-those with positive results for hysteroscopy and CD138 staining (DP), negative results for hysteroscopy but positive CD138 staining (SP), and negative results for hysteroscopy and CD138 staining (DN). The phenotypes of B cells and CD4+ T-cell subsets were analyzed using flow cytometry. RESULTS: CD38+ and CD138+ cells were mainly expressed in the non-leukocyte population of the endometria, and the endometrial CD19+ CD138+ B cells were fewer than the CD3+ CD138+ T cells. The percentage of Tfh cells increased with chronic inflammation in the endometria. Additionally, the elevated percentage of Tfh cells correlated with the number of miscarriages. CONCLUSIONS: CD4+ T cells, particularly Tfh cells, may be critical in chronic endometrial inflammation and affect its microenvironment, thereby regulating endometrial receptivity, compared to B cells.

Endometrial stromal cells from women with repeated implantation failure display impaired invasion towards trophoblastic spheroids.

In brief: Implantation failure can occur even after the transfer of good-quality embryos. This study showed that the migration of human endometrial stromal cells towards embryonic trophoblasts is higher in women with live births in the first in vitro fertilization cycle than those with repeated implantation failure, suggesting that the chemotactic response of stroma cells is associated with successful pregnancy. Abstract: The success rate of in vitro fertilization (IVF) remains limited in some women despite transfers of good-quality embryos in repeated attempts. There is no reliable tool for assessing endometrial receptivity. This study aimed to assess the interaction between decidualized human primary endometrial stromal cells (1°-EnSC) and human embryonic stem cell-derived trophoblastic spheroids (BAP-EB) and to compare the invasion ability of decidualized 1°-EnSC towards BAP-EB between women attaining live birth in the first IVF cycle and those with repeated implantation failure (RIF). The invasion of the decidualized human endometrial cell line (T-HESC) and 1°-EnSC towards BAP-EB was studied. Real-time quantitative PCR and immunocytochemistry were employed to determine the expression of decidualization markers at mRNA and protein levels, respectively. Trophoblast-like BAP-EB-96h, instead of early trophectoderm (TE)-like BAP-EB-48h, facilitated the invasion ability of decidualized T-HESC and decidualized 1°-EnSC. Human chorionic gonadotropin at supra-physiological levels promoted the invasiveness of decidualized 1°-EnSC. The extent of BAP-EB-96h-induced invasion was significantly stronger in decidualized 1°-EnSC from women who had a live birth in the first IVF cycle when compared to those with RIF. While no difference was found in the expression of decidualization markers, PRL and IGFBP1 among two groups of women, significantly lower HLA-B was detected in the non-decidualized and decidualized 1°-EnSC from women with RIF. Collectively, the findings suggested that the invasion of decidualized 1°-EnSC towards trophoblast-like BAP-EB-96h was higher in women who had a live birth in the first IVF cycle than those with RIF.

High-Throughput In Vitro Screening Identified Nemadipine as a Novel Suppressor of Embryo Implantation.

Current contraceptive methods interfere with folliculogenesis, fertilization, and embryo implantation by physical or hormonal approaches. Although hormonal contraceptive pills are effective in regulating egg formation, they are less effective in preventing embryo implantation. To explore the use of non-hormonal compounds that suppress embryo implantation, we established a high-throughput spheroid-endometrial epithelial cell co-culture assay to screen the Library of Pharmacologically Active Compounds (LOPAC) for compounds that affect trophoblastic spheroid (blastocyst surrogate) attachment onto endometrial epithelial Ishikawa cells. We identified 174 out of 1280 LOPAC that significantly suppressed BeWo spheroid attachment onto endometrial Ishikawa cells. Among the top 20 compounds, we found the one with the lowest cytotoxicity in Ishikawa cells, P11B5, which was later identified as Nemadipine-A. Nemadipine-A at 10 µM also suppressed BeWo spheroid attachment onto endometrial epithelial RL95-2 cells and primary human endometrial epithelial cells (hEECs) isolated from LH +7/8-day endometrial biopsies. Mice at 1.5 days post coitum (dpc) treated with a transcervical injection of 100 µg/kg Nemadipine-A or 500 µg/kg PRI-724 (control, Wnt-inhibitor), but not 10 µg/kg Nemadipine-A, suppressed embryo implantation compared with controls. The transcript expressions of endometrial receptivity markers, integrin αV (ITGAV) and mucin 1 (MUC1), but not ß-catenin (CTNNB1), were significantly decreased at 2.5 dpc in the uterus of treated mice compared with controls. The reduction of embryo implantation by Nemadipine-A was likely mediated through suppressing endometrial receptivity molecules ITGAV and MUC1. Nemadipine-A is a potential novel non-hormonal compound for contraception.

DNA Damage Response and Cell Cycle Regulation in Pluripotent Stem Cells.

Pluripotent stem cells (PSCs) hold great promise in cell-based therapy because of their pluripotent property and the ability to proliferate indefinitely. Embryonic stem cells (ESCs) derived from inner cell mass (ICM) possess unique cell cycle control with shortened G1 phase. In addition, ESCs have high expression of homologous recombination (HR)-related proteins, which repair double-strand breaks (DSBs) through HR or the non-homologous end joining (NHEJ) pathway. On the other hand, the generation of induced pluripotent stem cells (iPSCs) by forced expression of transcription factors (Oct4, Sox2, Klf4, c-Myc) is accompanied by oxidative stress and DNA damage. The DNA repair mechanism of DSBs is therefore critical in determining the genomic stability and efficiency of iPSCs generation. Maintaining genomic stability in PSCs plays a pivotal role in the proliferation and pluripotency of PSCs. In terms of therapeutic application, genomic stability is the key to reducing the risks of cancer development due to abnormal cell replication. Over the years, we and other groups have identified important regulators of DNA damage response in PSCs, including FOXM1, SIRT1 and PUMA. They function through transcription regulation of downstream targets (P53, CDK1) that are involved in cell cycle regulations. Here, we review the fundamental links between the PSC-specific HR process and DNA damage response, with a focus on the roles of FOXM1 and SIRT1 on maintaining genomic integrity.

Differential expression of protein disulfide isomerase (PDI) in regulating endometrial receptivity in humans.

Estrogen and progesterone regulate the expression of endometrial proteins that determine endometrial receptivity for embryo implantation. The protein disulfide isomerase (PDI) family of proteins play a diverse role in regulating protein modification and redox function. Although the role of PDIs in cancer progression has been widely studied, their role in endometrial receptivity is largely unknown. We have focused on the expressions of PDIA1, PDIA2, PDIA3, PDIA4, PDIA5, and PDIA6 isoforms in endometrial epithelium under the influence of estrogen and progesterone and investigated their functional role in regulating endometrial receptivity. We found PDIA1-6 transcripts were expressed in endometrial epithelial Ishikawa, RL95-2, AN3CA, and HEC1-B cell lines. The expression of PDIA1 was low and PDIA5 was high in HEC1-B cells, whereas PDIA2 was high in both AN3CA and HEC1-B cells. In Ishikawa cells, estrogen (10 and 100 nM) upregulated PDIA1 and PDIA6, whereas estrogen (100 nM) downregulated PDIA4 and PDIA5; and progesterone (0.1 and 1 µM) downregulated transcript expressions of PDIA1-6. In human endometrial samples, significantly lowered transcript expressions of PDIA2 and PDIA5 were observed in the secretory phase compared with the proliferative phase, whereas no change was observed in the other studied transcripts throughout the cycle. Inhibition of PDI by PDI antibody (5 and 10 µg/mL) and PDI inhibitor bacitracin (1 and 5 mM) significantly increased the attachment of Jeg-3 spheroids onto AN3CA cells. Taken together, our study suggests a role of PDI in regulating endometrial receptivity and the possibility of using PDI inhibitors to enhance endometrial receptivity.

Human embryonic stem cell-derived blastocyst-like spheroids resemble human trophectoderm during early implantation process.

OBJECTIVE: To study the use of human embryonic stem cell-derived trophoblastic spheroids (BAP-EB) as human blastocyst surrogates for studying early implantation and trophoblast development. DESIGN: Laboratory study. SETTING: University research laboratory. PATIENT(S): Infertile in vitro fertilization patients donating endometrial aspirates and human embryonic stem cells (hESCs: VAL3 and H9/WA09). INTERVENTION(S): In BAP-EB derived from hESC, transcriptomes analyzed by next-generation RNA sequencing, effects of Hippo signaling pathway studied by a YAP inhibitor, comparison of attachment of BAP-EB onto primary endometrial epithelial cells (EEC) collected at prereceptive and receptive phases, and antibody blocking assay used to study the molecule(s) involved in BAP-EB attachment. MAIN OUTCOME MEASURE(S): Gene expression profiles and endometrial cell attachment rates. RESULT(S): The BAP-EB differentiation protocol for VAL3 could be used to induce trophoblast differentiation in another hESC line, H9. Transcriptomic analysis showed that the epiblast signature gene expression was reduced while that of the trophoblast was induced during BAP-EB differentiation. Specifically, trophectoderm signature genes were induced in BAP-EB at 48 hours and 72 hours after induction of differentiation. The Hippo signaling pathway was one of the pathways induced during BAP-EB differentiation, and YAP1 inhibitor statistically significantly reduced attachment, outgrowth, and trophoblast gene expressions of BAP-EB. A statistically significantly higher number of BAP-EB derived from both VAL3 and H9 attached onto receptive EEC than prereceptive EEC. The antibody blocking assay demonstrated that endometrial E-cadherin might be critical in early implantation. CONCLUSION(S): The data suggest that BAP-EB possesses a trophectoderm-like signature, which supports the use of BAP-EB as a blastocyst surrogate for the study of trophoblast development and endometrial receptivity.

Independent association of serum vitamin D with anti-Mullerian hormone levels in women with polycystic ovary syndrome.

OBJECTIVE: This study aimed at investigating the association of serum vitamin D (25(OH)D) and anti-Mullerian hormone (AMH) levels in women with polycystic ovary syndrome (PCOS) as well as non-PCOS healthy ovulatory women and the possible confounding effects of adiposity and androgen. METHOD: This was a cross-sectional study conducted on serum samples collected from 451 women diagnosed with PCOS as well as 244 age-matched healthy ovulatory women in a tertiary gynaecology out-patient clinic and a family planning clinic. RESULTS: Serum 25(OH)D level was significantly higher in women recruited during summer and autumn than those recruited in winter and spring. Both serum 25(OH)D and AMH levels peaked during summer in women with PCOS. In ovulatory women, only serum 25(OH)D but not AMH level showed such seasonal variation. Serum 25(OH)D level in women with PCOS significantly correlated positively with AMH, AMH/antral follicle count (AFC) ratio, serum total testosterone, sex-hormone-binding globulin and quantitative insulin-sensitivity check index and inversely with body mass index (BMI), insulin, triglycerides and homeostatic model assessment of insulin resistance. After controlling for BMI, 25(OH)D level remained significantly correlated positively with serum AMH, AMH/AFC and total testosterone, and inversely with triglycerides. 25(OH)D level was an independent predictor of serum AMH level after controlling for age, BMI and free androgen index in women with PCOS. CONCLUSION: Serum 25(OH)D level is an independent factor significantly associated with AMH level in women with PCOS but not in ovulatory women.

Transcriptomic and methylomic analysis reveal the toxicological effect of 2,3,7,8-Tetrachlorodibenzodioxin on human embryonic stem cell.

Cumulating epidemiological studies demonstrated that environmental exposure to endocrine disrupting chemicals (EDCs) during the early stages of fetal development is associated with the increase in disease susceptibility in later life. The fetal developmental plasticity is considered as a protective mechanism against an undesirable prenatal environment. Dioxin is one of the environmental contaminants and is considered a diabetogenic factor. Experimental animal and human epidemiological studies have revealed that dioxin exposure was associated with insulin resistance and altered beta cell function. But the effect of dioxin exposure in early stage of fetal development is still largely unknown. In this report, we used the human embryonic stem cell (hESC) line, VAL-3, as a model, together with Methyl-CpG Binding Domain (MBD) protein-enriched genome sequencing and transcriptome sequencing (RNA-seq), in order to determine the dynamic changes of the epigenetic landscape and transcriptional dysregulation in hESC upon dioxin exposure. The bioinformatics analyses including the Database for Annotation, Visualization and Integrated Discovery (DAVID) analysis and Ingenuity Pathway Analysis (IPA) highlighted the predisposed neural, hepatic, cardiac and metabolic toxicological effects of dioxin during the fetal development.

Effect of ulipristal acetate and mifepristone at emergency contraception dose on the embryo-endometrial attachment using an in vitro human trophoblastic spheroid and endometrial cell co-culture model.

STUDY QUESTION: Do both ulipristal acetate (UPA) and mifepristone inhibit embryo-endometrial attachment at concentrations corresponding to the emergency contraception (EC) dose? SUMMARY ANSWER: Both UPA and mifepristone at concentrations corresponding to the EC dose do not have an inhibitory effect on embryo implantation, although mifepristone at a higher concentration appeared to have such an effect. WHAT IS KNOWN ALREADY: Levonorgestrel is commonly used for EC, but it only acts through inhibition of ovulation. UPA and mifepristone have higher efficacy as EC compared to levonorgestrel; while there is some suggestion that mifepristone may interfere with implantation, whether UPA has post-ovulatory action in inhibiting implantation is yet to be confirmed. STUDY DESIGN, SIZE, DURATION: An in vitro experimental study using trophoblastic spheroids made from JAr cell line as the embryo surrogate, and the Ishikawa cell line and primary human endometrial cells cultured to monolayer as the endometrial surrogate. The primary endometrial cells were collected from nine volunteer women in the mid-luteal phase with consent. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study was conducted in a university gynaecology unit. The JAr and Ishikawa cell lines (or primary endometrial cells) were treated with graded concentrations of UPA (0, 0.04, 0.4 and 4 µM) or mifepristone (0, 0.1, 1 and 10 µM) for 24 h. Embryo-endometrial attachment was studied using an in vitro JAr spheroid-endometrial co-culture model. Expressions of progesterone receptor, ß-catenin and glycogen synthase kinase 3 ß (GSK-3ß) were studied with real-time RT-PCR and Western blotting, respectively. MAIN RESULTS AND THE ROLE OF CHANCE: In the Ishikawa experiments, there was no significant difference in the JAr spheroid attachment rate after treatment with UPA at 0 (93.0%), 0.04 (93.6%), 0.4 (93.4%) and 4 (91.4%) µM concentrations (P > 0.05); the attachment rate was reduced after treatment with mifepristone only at 10 µM (79.8%, P < 0.0001) but not at 0.1 (92.1%) or 1.0 (95.2%) µM concentrations. In the primary endometrial cell experiments, again no significant difference was observed in the JAr spheroid attachment rate after treatment with UPA 4 µM (42.6%) compared to control (46.5%, P > 0.05). Both UPA and mifepristone could significantly up-regulate progesterone receptor expression. There was no significant alteration in expression of ß-catenin and GSK-3ß after treatment with UPA 4 µM or mifepristone 10 µM (P > 0.05). LIMITATIONS, REASONS FOR CAUTION: The co-culture model is only a surrogate which may not fully represent the complicated process of embryo implantation in vivo, although there is no existing perfect model for studying implantation in vitro which fully resembles the latter. WIDER IMPLICATIONS OF THE FINDINGS: The lack of inhibitory effect on embryo implantation by UPA and possibly mifepristone at concentrations corresponding to the EC dose is an important information for contraceptive counseling. STUDY FUNDING/COMPETING INTEREST(S): We had free supply of the UPA compound used in this study from Laboratoire HRA Pharma. This work was supported by a Seed Fund from the Centre of Reproduction, Development and Growth, Faculty of Medicine, The University of Hong Kong, Hong Kong.

The effect of 7 days of letrozole pretreatment combined with misoprostol on the expression of progesterone receptor and apoptotic factors of placental and decidual tissues from first-trimester abortion: a randomized controlled trial.

OBJECTIVE: To evaluate if letrozole-induced suppression of estradiol reduces progesterone receptor expression and apoptosis in the first-trimester placenta. STUDY DESIGN: We performed a double-blinded, randomized, placebo-controlled trial. We randomized 20 women requesting first-trimester abortion with gestation up to 63 days to receive either letrozole 10 mg daily or placebo pretreatment for 7 days before administrating 400 mcg of vaginal misoprostol followed by suction abortion. We collected the placental and decidual tissues on which we performed immunohistochemical staining for progesterone receptor and apoptotic markers (active caspase 3, caspase 3, Bcl2, CD95, fas ligand) and determined H-scores of each based on the intensities of staining. We performed terminal deoxynucleotidyl transferase-mediated dUTP-digoxigenin nick end labeling (TUNEL) assay for apoptosis in the samples of four women to confirm the findings from apoptotic markers. RESULTS: We excluded one woman in the letrozole group from the analysis because she had passage of abortus after taking letrozole, leaving 19 women (9 in the letrozole group, 10 in the placebo group) for analysis. There was no significant difference in the H-scorings of progesterone receptor and apoptotic markers, as well as proportion of apoptotic cells on TUNEL assay between the two groups. The H-scores for the progesterone receptor were 8.17 ± 2.67 (mean ± SD) in the letrozole group and 9.01 ± 2.82 in the placebo group (p=0.36). CONCLUSION: We did not detect a difference in the expression of progesterone receptor and apoptotic markers in placental and decidual tissues after letrozole pretreatment for 7 days in first-trimester abortion. IMPLICATIONS: We did not confirm the hypothesis that letrozole reduces progesterone receptor expression and induces apoptosis in the first-trimester placenta. Further studies are required to allow better understanding of the mechanism by which estrogen suppression following the use of letrozole can lead to improved abortion rate in the first trimester.

Ovarian response and cumulative live birth rate of women undergoing in-vitro fertilisation who had discordant anti-Mullerian hormone and antral follicle count measurements: a retrospective study.

OBJECTIVE: To evaluate ovarian response and cumulative live birth rate of women undergoing in-vitro fertilization (IVF) treatment who had discordant baseline serum anti-Mullerian hormone (AMH) level and antral follicle count (AFC). METHODS: This is a retrospective cohort study on 1,046 women undergoing the first IVF cycle in Queen Mary Hospital, Hong Kong. Subjects receiving standard IVF treatment with the GnRH agonist long protocol were classified according to their quartiles of baseline AMH and AFC measurements after GnRH agonist down-regulation and before commencing ovarian stimulation. The number of retrieved oocytes, ovarian sensitivity index (OSI) and cumulative live-birth rate for each classification category were compared. RESULTS: Among our studied subjects, 32.2% were discordant in their AMH and AFC quartiles. Among them, those having higher AMH within the same AFC quartile had higher number of retrieved oocytes and cumulative live-birth rate. Subjects discordant in AMH and AFC had intermediate OSI which differed significantly compared to those concordant in AMH and AFC on either end. OSI of those discordant in AMH and AFC did not differ significantly whether either AMH or AFC quartile was higher than the other. CONCLUSIONS: When AMH and AFC are discordant, the ovarian responsiveness is intermediate between that when both are concordant on either end. Women having higher AMH within the same AFC quartile had higher number of retrieved oocytes and cumulative live-birth rate.

Effect of preovulatory progesterone elevation and duration of progesterone elevation on the pregnancy rate of frozen-thawed embryo transfer in natural cycles.

OBJECTIVE: To assess the incidence of P elevation (PE) in natural cycles and evaluate its effect on frozen-thawed embryo transfer cycles performed in natural cycles (FET-NC). STUDY DESIGN: Retrospective analysis. SETTING: A tertiary assisted reproductive unit. PATIENT(S): Subfertile woman who did not conceive in their stimulated IVF cycle and underwent the first FET-NC cycle. INTERVENTION(S): Achieved serum samples were assayed for P concentrations from the day of LH surge up to 3 days before the surge. The cutoff level of PE was defined as 5 nmol/L. MAIN OUTCOME MEASURE(S): Clinical and ongoing pregnancy rates. RESULT(S): The incidence of PE in natural cycles was 173 of 610 (28.4%). There were no significant differences in both clinical and ongoing pregnancy rates (39.0% vs. 37.3% and 32.5% vs. 31.7%) between those with vs. without PE on the day of LH surge. If PE lasted for 2 days or more, there was a significant reduction in the clinical pregnancy rate (39.4% vs. 20.7%). Using multivariate logistic regression, women's age, PE for 2 days or more, and the number of top-quality embryos were the significant factors for clinical pregnancy rates in FET-NC. CONCLUSION(S): The incidence of PE in FET-NC was similar to that in stimulated cycles. Progesterone elevation for 2 days or more before the LH surge impaired the clinical pregnancy rate of FET-NC, whereas PE on the day of LH surge only did not have such an adverse effect.

Cumulative live-birth rate in women with polycystic ovary syndrome or isolated polycystic ovaries undergoing in-vitro fertilisation treatment.

PURPOSE: This retrospective cohort study evaluated the cumulative live birth rate in women with polycystic ovary syndrome (PCOS) and isolated polycystic ovaries (PCO) undergoing in-vitro fertilisation (IVF) treatment. METHODS: We studied 104 women with PCOS, 184 with PCO and 576 age-matched controls undergoing the first IVF treatment cycle between 2002 and 2009. The main outcome measure was cumulative live birth in the fresh plus all the frozen embryo transfers combined after the same stimulation cycle. RESULTS: Women in both the PCOS (n = 104) and isolated PCO groups (n = 184) had higher ovarian response parameters compared to age-matched controls (n = 576), and higher rates of withholding fresh embryo transfer for risk of ovarian hyperstimulation syndrome (OHSS). The actual incidence of moderate to severe OHSS was significantly higher in the PCOS (11.5 %) but not the isolated PCO group (8.2%) compared to controls (4.9%). The live birth rates in the fresh cycle were comparable among the 3 groups, but the PCOS group had a significantly higher miscarriage rate compared to the other 2 groups. Cumulative live birth rate was significantly higher in the isolated PCO group (60.3%), but not the PCOS group (50.0%), compared to controls (47.5%). CONCLUSIONS: Women in the isolated PCO group, but not the PCOS group, had a significantly higher cumulative live birth rate compared to controls. This could be explained by the quantitative effect of the higher number of transferable embryos obtained per stimulation cycle, which is uncompromised by the unfavourable embryo competence otherwise observed in PCOS.

The effect of letrozole with misoprostol for medical termination of pregnancy on the expression of steroid receptors in the placenta.

STUDY QUESTION: What is the effect of letrozole on the expression of steroid receptors in the placentae in cases of termination of pregnancies? SUMMARY ANSWER: The expression of estrogen receptor-α (ERα) and progesterone receptor (PR) transcripts, as well as ERα protein, in placentae was suppressed by letrozole pretreatment in second trimester termination of pregnancy. WHAT IS KNOWN ALREADY: There have been no data in the literature on the effect of letrozole in termination of human pregnancies. STUDY DESIGN, SIZE, DURATION: This study is part of a clinical randomized trial in which 50 subjects were recruited and 44 placentae were collected. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women (n = 50) requesting second trimester abortion between 12 and 20 gestational weeks were randomized to receive either letrozole or placebo pretreatment for 3 days before administration of vaginal misoprostol. Placentae were collected from both groups of women after the abortion. Total RNA from the frozen placenta samples was extracted and subjected to real-time RT-PCR analysis of ERα and estrogen receptor-ß (ERß), PR and glucocorticoid receptor (GR) transcripts. Immunohistochemical studies of ERα, ERß, PR and GR expression, as well as Ki67 and PCNA staining for proliferation, were performed. TUNEL assays were performed to determine the extent of apoptosis. MAIN RESULTS AND THE ROLE OF CHANCE: Real-time RT-PCR demonstrated that the median ERα {3.900 [95% confidence interval (CI): -0.643-8.443] in the letrozole group versus 4.714 (95% CI: 1.776-7.652) in the control group; P = 0.005} and the median PR [0.701 (95% CI: 0.333-1.069) in the letrozole group versus 1.774 (95% CI: 1.07-2.478) in the control group; P = 0.003] were significantly lower in the letrozole group compared with the control group. Furthermore, ERα protein levels, in both syncytiotrophoblasts and cytotrophoblasts but not in villous stromal cells, were significantly reduced [H-score of 113 (95% CI: 103-119) in the letrozole group versus 217 (95% CI: 214-290) in the control group, in syncytiotrophoblasts; 100 (95% CI: 98-105) in the letrozole group versus 210 (95% CI: 200-286) in the control group, in cytotrophoblasts; P = 0.004], while the expression levels of ERß, PR, GR, PCNA, Ki67 and TUNEL were not significantly different between the two groups. LIMITATIONS, REASONS FOR CAUTION: Only the placentae from the second trimester termination of pregnancy were collected in this study. Information from first trimester terminations is still lacking. WIDER IMPLICATIONS OF THE FINDINGS: The results shed some light on the mechanism of action of letrozole pretreatment in termination of pregnancies. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by the GRF/RGC and CRCG grants of the University of Hong Kong. TRIAL REGISTRATION NUMBER: HKClinicalTrials.com with trial number HKCTR-695.

Evaluation of serum antimullerian hormone and inhibin B concentrations in the differential diagnosis of secondary oligoamenorrhea.

OBJECTIVE: To evaluate the performance of antimullerian hormone (AMH) and inhibin B as ovarian function markers for differentiating common causes of secondary oligoamenorrhea, namely hypogonadotrophic hypogonadism (HH), polycystic ovary syndrome (PCOS), premature ovarian failure (POF), and hyperprolactinemia (HPRL). DESIGN: Retrospective analysis. SETTING: Two university hospitals. PATIENT(S): A total of 124 women with secondary oligoamenorrhea and 26 women with normal ovulation. INTERVENTION(S): Serum samples from the subjects were analyzed for AMH and inhibin B. MAIN OUTCOME MEASURE(S): Serum AMH and inhibin B concentrations. RESULT(S): Serum AMH concentration was significantly raised in women having World Health Organization group 2 anovulation, either with or without PCOS, and was significantly decreased to very low levels in POF; the diagnostic accuracy in both conditions was excellent, with areas under the receiver operating characteristic curve (AUC) of 0.913 and 0.977, respectively. The discriminatory performance between HH and PCOS was also good, with AUC 0.861. AMH remained unchanged in HH and HPRL compared with ovulatory control subjects. There were large overlap of serum inhibin B levels in the different conditions, and a significant difference from control subjects existed only in the POF group. CONCLUSION(S): Serum AMH, but not inhibin B concentration, serves as a useful diagnostic tool in the differential diagnosis of secondary oligoamenorrhea.

Sequential use of letrozole and gonadotrophin in women with poor ovarian reserve: a randomized controlled trial.

Sequential use of letrozole and human menopausal gonadotrophin (HMG) was compared with HMG only in poor ovarian responders undergoing IVF. Patients (n=53) with less than four oocytes retrieved in previous IVF cycles or less than five antral follicles were randomized to either letrozole for 5days followed by HMG or HMG alone. The letrozole group had lower dosage of HMG (P<0.001), shorter duration of HMG (P<0.001) and fewer oocytes (P=0.001) when compared with controls. Live-birth rate was comparable with a lower miscarriage rate in the letrozole group (P=0.038). Serum FSH concentrations were comparable in both groups except on day 8, while oestradiol concentrations were all lower in the letrozole group from day 4 (all P<0.001). Follicular fluid concentrations of testosterone, androstenedione, FSH and anti-Müllerian hormone were higher in the letrozole group (P=0.009, P=0.001, P=0.046 and P=0.034, respectively). Compared with HMG alone, sequential use of letrozole and HMG in poor responders resulted in significantly lower total dosage and shorter duration of HMG, a comparable live-birth rate, a significantly lower miscarriage rate and a more favourable hormonal environment of follicular fluid. The management of poor ovarian responders or women with poor ovarian reserve in IVF is controversial. The use of letrozole has been studied; however, results are inconsistent. This randomized trial studied the sequential use of letrozole and gonadotrophin compared with gonadotrophin alone in poor responders undergoing IVF. The sequential use of letrozole and gonadotrophin led to a significantly lower dosage and shorter duration of gonadotrophin use, significantly fewer oocytes, comparable live-birth rate, a significantly lower miscarriage rate and a more favourable hormonal environment at a lower cost.

Identification of cells with colony-forming activity, self-renewal capacity, and multipotency in ovarian endometriosis.

Endometriosis, the growth of endometrial tissue outside the uterine cavity, is a common gynecological disorder affecting 10% to 15% of women in their reproductive years. Retrograde menstrual shedding containing endometrial stem/progenitor cells has been postulated to be involved in its pathogenesis. In this study, we identified putative endometriotic stem/progenitor cells by their colony-forming potential, self-renewal capacity, and multipotency. Purified epithelial and stromal cells isolated from ovarian endometriotic cysts formed large and small colony-forming units (CFUs) in clonogenic assay. The colony-forming activity of epithelial and stromal cells was found to differ greatly between autologous endometrium and ovarian endometrioma samples. The large CFUs could propagate more than the small CFUs. The endometriotic epithelial small CFUs expressed epithelial markers (epithelial cell adhesion molecule, cytokeratin, and α6 integrin); only occasional large CFUs expressed α6 integrin. Aside from the expression of fibroblast markers, stromal CFUs also expressed three somatic stem cell markers: sal-like 4, CD133, and Musashi-1. Endometriotic stromal cells derived from large CFUs could differentiate into four mesenchymal lineages when cultured in the respective inducing-media, as determined by histochemical staining and RT-PCR of lineage specific markers. These findings demonstrate that ovarian endometrioma contains a subset of cells displaying somatic stem cell properties.