RNA 5-Methylcytosine Facilitates the Maternal-to-Zygotic Transition by Preventing Maternal mRNA Decay.

The maternal-to-zygotic transition (MZT) is a conserved and fundamental process during which the maternal environment is converted to an environment of embryonic-driven development through dramatic reprogramming. However, how maternally supplied transcripts are dynamically regulated during MZT remains largely unknown. Herein, through genome-wide profiling of RNA 5-methylcytosine (m5C) modification in zebrafish early embryos, we found that m5C-modified maternal mRNAs display higher stability than non-m5C-modified mRNAs during MZT. We discovered that Y-box binding protein 1 (Ybx1) preferentially recognizes m5C-modified mRNAs through π-π interactions with a key residue, Trp45, in Ybx1's cold shock domain (CSD), which plays essential roles in maternal mRNA stability and early embryogenesis of zebrafish. Together with the mRNA stabilizer Pabpc1a, Ybx1 promotes the stability of its target mRNAs in an m5C-dependent manner. Our study demonstrates an unexpected mechanism of RNA m5C-regulated maternal mRNA stabilization during zebrafish MZT, highlighting the critical role of m5C mRNA modification in early development.

The role of amphiregulin in ovarian function and disease.

Amphiregulin (AREG) is an epidermal growth factor (EGF)-like growth factor that binds exclusively to the EGF receptor (EGFR). Treatment with luteinizing hormone (LH) and/or human chorionic gonadotropin dramatically induces the expression of AREG in the granulosa cells of the preovulatory follicle. In addition, AREG is the most abundant EGFR ligand in human follicular fluid. Therefore, AREG is considered a predominant propagator that mediates LH surge-regulated ovarian functions in an autocrine and/or paracrine manner. In addition to the well-characterized stimulatory effect of LH on AREG expression, recent studies discovered that several local factors and epigenetic modifications participate in the regulation of ovarian AREG expression. Moreover, aberrant expression of AREG has recently been reported to contribute to the pathogenesis of several ovarian diseases, such as ovarian hyperstimulation syndrome, polycystic ovary syndrome, and epithelial ovarian cancer. Furthermore, increasing evidence has elucidated new applications of AREG in assisted reproductive technology. Collectively, these studies highlight the importance of AREG in female reproductive health and disease. Understanding the normal and pathological roles of AREG and elucidating the molecular and cellular mechanisms of AREG regulation of ovarian functions will inform innovative approaches for fertility regulation and the prevention and treatment of ovarian diseases. Therefore, this review summarizes the functional roles of AREG in ovarian function and disease.

Effects of hepatitis B virus infection on the treatment outcomes following in vitro fertilization/intracytoplasmic sperm injection: An analysis of 21,999 first embryo transfer cycles.

To investigate the effects of hepatitis B virus (HBV) infection on the outcomes of Chinese couples undergoing in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) and the clinical data of their neonates. A total of 21,999 first embryo transfer cycles were included. They were categorized into four groups based on the couple's hepatitis B surface antigen (HBsAg) result (Group A = female HBsAg- and male HBsAg- ; Group B = female HBsAg+ and male HBsAg- ; Group C = female HBsAg- and male HBsAg+ ; Group D = female HBsAg+ and male HBsAg+ ). The fertilization rate (FR), cleavage rate (CR), implantation rate (IPR), clinical pregnancy rate (CPR), live birth rate (LBR) and miscarriage rate (MCR) were analysed. Multilevel logistic regression was applied to evaluate the association. The total prevalence of HBV infection was 5.74% (2526/43998). There were no statistically significant differences in CRs (98.69%, 98.76%, 98.66%, 98.72%, p > .05), IPRs (45.86%, 47.33%, 45.19%, 39.61%, p > .05), CPRs (62.84%, 65.05%, 61.80%, 56.81%, p > .05), MCRs (12.70%, 11.99%, 12.58%, 4%, p > .05) and LBRs (53.43%, 55.38%, 52.70%, 54.54%, p > .05) among the four groups. However, there were significant differences in FRs (66.25%, 66.55%, 66.32%, 61.92%, p < .05). Group D had the lowest FR. After adjusting for confounders, the multilevel logistic regression showed that HBsAg+ had no impact on the LBR, CPR or MCR. We also analysed the data of 14,465 newborns, including 8593 singletons and 2936 twins. Among the four groups, no variables reached statistical significance, including neonatal birth weight (NBW), twin ratio, gestational age, premature birth, delivery type, fetal macrosomia or low birth weight (p > .05). Our study demonstrates that, although biparental HBV infection may affect the FR, neither single-parent infection nor biparental HBV infection affects IVF/ICSI outcomes or neonatal outcomes.

TGF-ß1 upregulates secreted protein acidic and rich in cysteine expression in human granulosa-lutein cells: a potential mechanism for the pathogenesis of ovarian hyperstimulation syndrome.

BACKGROUND: Ovarian hyperstimulation syndrome (OHSS) is a serious complication during in vitro fertilization (IVF) treatment. The upregulation of ovarian transforming growth factor-beta 1 (TGF-ß1) is involved in the development of OHSS. The secreted protein acidic and rich in cysteine (SPARC) is a secreted multifunctional matricellular glycoprotein. Although the regulatory effects of TGF-ß1 on SPARC expression have been reported, whether TGF-ß1 regulates SPARC expression in the human ovary remains unknown. In addition, the role of SPARC in the pathogenesis of OHSS is unclear. METHODS: A steroidogenic human ovarian granulosa-like tumor cell line, KGN, and primary culture of human granulosa-lutein (hGL) cells obtained from patients undergoing IVF treatment were used as experimental models. OHSS was induced in rats, and ovaries were collected. Follicular fluid samples were collected from 39 OHSS and 35 non-OHSS patients during oocyte retrieval. The underlying molecular mechanisms mediating the effect of TGF-ß1 on SPARC expression were explored by a series of in vitro experiments. RESULTS: TGF-ß1 upregulated SPARC expression in both KGN and hGL cells. The stimulatory effect of TGF-ß1 on SPARC expression was mediated by SMAD3 but not SMAD2. The transcription factors, Snail and Slug, were induced in response to the TGF-ß1 treatment. However, only Slug was required for the TGF-ß1-induced SPARC expression. Conversely, we found that the knockdown of SPARC decreased Slug expression. Our results also revealed that SPARC was upregulated in the OHSS rat ovaries and in the follicular fluid of OHSS patients. Knockdown of SPARC attenuated the TGF-ß1-stimulated expression of vascular endothelial growth factor (VEGF) and aromatase, two markers of OHSS. Moreover, the knockdown of SPARC reduced TGF-ß1 signaling by downregulating SMAD4 expression. CONCLUSIONS: By illustrating the potential physiological and pathological roles of TGF-ß1 in the regulation of SPARC in hGL cells, our results may serve to improve current strategies used to treat clinical infertility and OHSS. Video Abstract.

Epigallocatechin-3-gallate stimulates StAR expression and progesterone production in human granulosa cells through the 67-kDa laminin receptor-mediated CREB signaling pathway.

Epigallocatechin-3-gallate (EGCG) is the most abundant and biologically active catechins extracted from green tea. The health benefits of EGCG have been extendedly studied. Ovarian steroidogenesis plays a pivotal role in maintaining normal reproductive function. Granulosa cells in the ovary are essential for steroid hormone production. To date, the effect of EGCG on steroidogenesis in human granulosa cells remains unclear. In the present study, we examine the physiological concentrations of EGCG on steroidogenesis in a steroidogenic human granulosa-like tumor cell line, KGN. Our results demonstrate that treatment with EGCG upregulates steroidogenic acute regulatory protein (StAR) expression and increases progesterone (P4) production. EGCG does not affect the expression levels of other steroidogenesis-related enzymes, such as P450 side-chain cleavage enzyme, 3ß-hydroxysteroid dehydrogenase, and aromatase. In addition, we identify the expression of 67-kDa laminin receptor (67LR) in KGN cells. Moreover, EGCG-induced StAR expression and P4 production require the 67LR-mediated activation of the PKA-CREB signaling pathway. These results provide a better understanding of the function of EGCG on ovarian steroidogenesis, which may lead to the development of alternative therapeutic approaches for reproductive disorders.

TGF-ß1 inhibits human trophoblast cell invasion by upregulating kisspeptin expression through ERK1/2 but not SMAD signaling pathway.

BACKGROUND: Tightly regulation of extravillous cytotrophoblast (EVT) cell invasion is critical for the placentation and establishment of a successful pregnancy. Insufficient EVT cell invasion leads to the development of preeclampsia (PE) which is a leading cause of maternal and perinatal mortality and morbidity. Transforming growth factor-beta1 (TGF-ß1) and kisspeptin are expressed in the human placenta and have been shown to inhibit EVT cell invasion. Kisspeptin is a downstream target of TGF-ß1 in human breast cancer cells. However, whether kisspeptin is regulated by TGF-ß1 and mediates TGF-ß1-suppressed human EVT cell invasion remains unclear. METHODS: The effect of TGF-ß1 on kisspeptin expression and the underlying mechanisms were explored by a series of in vitro experiments in a human EVT cell line, HTR-8/SVneo, and primary cultures of human EVT cells. Serum levels of TGF-ß1 and kisspeptin in patients with or without PE were measured by ELISA. RESULTS: TGF-ß1 upregulates kisspeptin expression in HTR-8/SVneo cells and primary cultures of human EVT cells. Using pharmacological inhibitor and siRNA, we demonstrate that the stimulatory effect of TGF-ß1 on kisspeptin expression is mediated via the ALK5 receptor. Treatment with TGF-ß1 activates SMAD2/3 canonical pathways as well as ERK1/2 and PI3K/AKT non-canonical pathways. However, only inhibition of ERK1/2 activation attenuates the stimulatory effect of TGF-ß1 on kisspeptin expression. In addition, siRNA-mediated knockdown of kisspeptin attenuated TGF-ß1-suppressed EVT cell invasion. Moreover, we report that serum levels of TGF-ß1 and kisspeptin are significantly upregulated in patients with PE. CONCLUSIONS: By illustrating the potential physiological role of TGF-ß1 in the regulation of kisspeptin expression, our results may serve to improve current strategies used to treat placental diseases.

GDF-11 promotes human trophoblast cell invasion by increasing ID2-mediated MMP2 expression.

BACKGROUND: Growth differentiation factor-11 (GDF-11), also known as bone morphogenetic protein-11, belongs to the transforming growth factor-beta superfamily. GDF-11 was first identified as an important regulator during embryonic development. Increasing evidence has demonstrated that GDF-11 regulates the development of various organs and its aberrant expressions are associated with the risk of cardiovascular diseases and cancers. Extravillous trophoblast (EVT) cells invasion is a critical event for placenta development and needs to be finely regulated. However, to date, the biological function of GDF-11 in the human EVT cells remains unknown. METHODS: HTR-8/SVneo, a human EVT cell line, and primary cultures of human EVT cells were used to examine the effect of GDF-11 on matrix metalloproteinase 2 (MMP2) expression. Matrigel-coated transwell invasion assay was used to examine cell invasiveness. A series of in vitro experiments were applied to explore the underlying mechanisms that mediate the effect of GDF-11 on MMP2 expression and cell invasion. RESULTS: Treatment with GDF-11 stimulates MMP2 expression, in the HTR-8/SVneo and primary human EVT cells. Using a pharmacological inhibitor and siRNA-mediated knockdown approaches, our results demonstrated that the stimulatory effect of GDF-11 on MMP2 expression was mediated by the ALK4/5-SMAD2/3 signaling pathways. In addition, the expression of inhibitor of DNA-binding protein 2 (ID2) was upregulated by GDF-11 and that was required for the GDF-11-stimulated MMP2 expression and EVT cell invasion. CONCLUSIONS: These findings discover a new biological function and underlying molecular mechanisms of GDF-11 in the regulation of human EVT cell invasion. Video Abstract.

HB-EGF upregulates StAR expression and stimulates progesterone production through ERK1/2 signaling in human granulosa-lutein cells.

BACKGROUND: Heparin-binding epidermal growth factor-like growth factor (HB-EGF) belongs to the epidermal growth factor (EGF) family of growth factors. HB-EGF and its receptors, epidermal growth factor receptor (EGFR) and HER4, are expressed in the human corpus luteum. HB-EGF has been shown to regulate luteal function by preventing cell apoptosis. Steroidogenesis is the primary function of the human corpus luteum. Steroidogenic acute regulatory protein (StAR) plays a critical role in steroidogenesis. StAR expression and progesterone (P4) production in human granulosa-lutein (hGL) cells have been shown to be upregulated by a ligand of EGFR, amphiregulin. However, whether HB-EGF can achieve the same effects remains unknown. METHODS: A steroidogenic human ovarian granulosa-like tumor cell line, KGN, and primary culture of hGL cells obtained from patients undergoing in vitro fertilization treatment were used as experimental models. The underlying molecular mechanisms mediating the effects of HB-EGF on StAR expression and P4 production were explored by a series of in vitro experiments. RESULTS: Western blot showed that EGFR, HER2, and HER4 were expressed in both KGN and hGL cells. Treatment with HB-EGF for 24 h induced StAR expression but did not affect the expression of steroidogenesis-related enzymes, P450 side chain cleavage enzyme, 3ß-hydroxysteroid dehydrogenase, and aromatase. Using pharmacological inhibitors and a siRNA-mediated knockdown approach, we showed that EGFR, HER4, but not HER2, were required for HB-EGF-stimulated StAR expression and P4 production. In addition, HB-EGF-induced upregulations of StAR expression and P4 production were mediated by the activation of the ERK1/2 signaling pathway. CONCLUSION: This study increases the understanding of the physiological role of HB-EGF in human luteal functions. Video Abstract.

A meta-analysis of serum lipid profiles in premature ovarian insufficiency.

Premature ovarian insufficiency (POI), defined as loss of normal ovarian functions before the age of 40 years, occurs in at least 1% of all women. It affects the reproductive system and causes many health problems and psychological stress. Abnormal serum lipid profile leads to cardiovascular diseases, which are strongly associated with high mortality in patients with POI. To date, several studies have examined the levels of different serum lipids in patients with POI. The results, however, are either inconclusive or inconsistent. Therefore, the aim of this meta-analysis was to measure whether serum levels of total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglyceride are varied in patients with POI. Ten studies in total were included in this meta-analysis involving 1009 individuals: 458 patients with POI and 551 controls. Our analysis results showed that serum total cholesterol (P < 0.00001), LDL-C (P < 0.0001), and triglyceride (P = 0.01) levels were significantly higher in patients with POI compared with healthy controls. Serum HDL-C levels, however, did not vary significantly between controls and patients with POI. These results suggest that elevations in unfavourable lipids may contribute to the high risk of cardiovascular diseases that are observed in patients with POI.

Comparison of embryo implantation potential between time-lapse incubators and standard incubators: a randomized controlled study.

RESEARCH QUESTION: What are the potential clinical benefits of embryo culture and assessment in a time-lapse incubator compared with a standard incubator using static assessment? DESIGN: This large multicentre, single-blinded, randomized controlled study included 1224 participants randomly assigned (1:1) to the time-lapse or standard incubator group. In all patients one or two embryos were transferred on day 3. The primary outcome was the implantation rate in the first embryo transfer cycle. Secondary outcomes included the cumulative implantation rate, live birth rate in the first embryo transfer cycle and cumulative live birth rate. RESULTS: Among 1224 participants recruited, 1182 underwent embryo transfer. The number of successfully implanted embryos in the first transfer cycle was significantly higher in the time-lapse incubator group (time-lapse group: 52.35%, standard incubator group: 47.11%, P = 0.014). The implantation rate in the first embryo transfer cycle was still significantly higher in the time-lapse group than the standard incubator group after adjusting for age, body mass index, medical centre and embryo status (relative risk 1.11, 95% confidence interval 1.02-1.20, P = 0.020). However, the cumulative implantation rate, live birth rate in the first embryo transfer cycle and cumulative live birth rate were not statistically different between the groups. CONCLUSIONS: The implantation rate in the first embryo transfer cycle was significantly improved in the time-lapse group, but the effect of the time-lapse system on the cumulative implantation rate or cumulative live birth rate was not significant. The embryo assessment method offered by time-lapse systems rather than an undisturbed environment may play an important role in improving the implantation rate in the first embryo transfer cycle. These results are only applicable to young patients.

Placensin is a glucogenic hormone secreted by human placenta.

FBN1 encodes asprosin, a glucogenic hormone, following furin cleavage of the C-terminus of profibrillin 1. Based on evolutionary conservation between FBN1 and FBN2, together with conserved furin cleavage sites, we identified a peptide hormone placensin encoded by FBN2 based on its high expression in trophoblasts of human placenta. In primary and immortalized murine hepatocytes, placensin stimulates cAMP production, protein kinase A (PKA) activity, and glucose secretion, accompanied by increased expression of gluconeogenesis enzymes. In situ perfusion of liver and in vivo injection with placensin also stimulate glucose secretion. Placensin is secreted by immortalized human trophoblastic HTR-8/SVneo cells, whereas placensin treatment stimulates cAMP-PKA signaling in these cells, accompanied by increases in MMP9 transcripts and activities, thereby promoting cell invasion. In pregnant women, levels of serum placensin increase in a stage-dependent manner. During third trimester, serum placensin levels of patients with gestational diabetes mellitus are increased to a bigger extent compared to healthy pregnant women. Thus, placensin represents a placenta-derived hormone, capable of stimulating glucose secretion and trophoblast invasion.

TGF-ß1 stimulates aromatase expression and estradiol production through SMAD2 and ERK1/2 signaling pathways in human granulosa-lutein cells.

Estradiol (E2), one of the main steroid hormones secreted by the ovaries, plays an important role in maintaining normal female reproductive function. Ovarian granulosa cells are the main source of E2 production because these cells express aromatase, which is encoded by the CYP19A1 gene and catalyzes the final step in E2 biosynthesis from androgens. Transforming growth factor-beta 1 (TGF-ß1) and its receptors are expressed in human granulosa cells, and TGF-ß1 expression can be detected in human follicular fluid. To date, TGF-ß1 has been shown to regulate various ovarian functions. However, whether aromatase can be regulated by TGF-ß1 in human granulosa cells has not been determined. In the present study, we demonstrate that TGF-ß1 stimulates aromatase expression in primary human granulosa-lutein cells and in the human ovarian granulose-like tumor cell line, KGN. We used pharmacological inhibitors and small interfering RNA-mediated knockdown approaches to reveal that the SMAD2 and ERK1/2 signaling pathways are involved in TGF-ß1-induced aromatase expression and E2 production. These results not only provide important insights into the molecular mechanisms that mediate TGF-ß1-induced aromatase expression and E2 production in human granulosa cells but also increase the understanding of the normal physiological roles of TGF-ß1 in the ovary.

GDF-8 stimulates trophoblast cell invasion by inducing ALK5-SMAD2/3-mediated MMP2 expression.

Matrix metalloproteinases (MMPs) play a pivotal role in the regulation of cell invasion. Placental trophoblast cell invasion is a precisely regulated event. Dysregulation of MMPs has been linked to various placental diseases. Growth differentiation factor-8 (GDF-8), also known as myostatin, is a member of the transforming growth factor-beta (TGF-ß) superfamily. GDF-8 and its putative receptors are expressed in human extravillous cytotrophoblast cells (EVTs). Although the pro-invasive effect of GDF-8 in human EVT cells has been recently reported, the underlying molecular mechanism remains largely unknown. In this study, we investigate the effects of GDF-8 on the expression of the two most important MMPs, MMP2 and MMP9, in the HTR-8/SVneo human EVT cell line. Our results show that GDF-8 significantly upregulates the expression of MMP2. The expression of MMP9 is not affected by GDF-8. Using a siRNA-mediated knockdown approach, we reveal that the stimulatory effect of GDF-8 on MMP2 expression is mediated by the ALK5-SMAD2/3 signaling pathway. Additionally, the knockdown of MMP2 attenuates the GDF-8-induced cell invasiveness. These findings deepen our understanding of the biological roles of GDF-8 in the regulation of human trophoblast cell invasion.

EGF stimulates human trophoblast cell invasion by downregulating ID3-mediated KISS1 expression.

BACKGROUND: During pregnancy, trophoblast cell invasion needs to be finely controlled. Aberrant trophoblast cell invasion is associated with placental diseases. Epidermal growth factor (EGF) and its receptor, EGFR, are expressed in trophoblast cells. Although the pro-invasive effect of EGF on trophoblast cells has been reported, the underlying mechanism remains largely unknown. RESULTS: In the present study, we conducted an RNA sequencing (RNA-seq) to HTR-8/SVneo human trophoblast cells in response to EGF and identified KISS1 as a target gene of EGF. The human KISS1 gene encodes kisspeptin, also known as metastin, which can suppress tumor metastasis. Our results showed that EGF treatment downregulated KISS1 expression and secretion by activating the EGFR-mediated PI3K/AKT signaling pathway. In addition, the expression of inhibitor of DNA-binding protein 3 (ID3) was downregulated by EGF and that was required for the EGF-suppressed KISS1 expression. Functionally, transwell invasion assays demonstrated that EGF stimulated human trophoblast cell invasion by downregulating KISS1 expression. Preeclampsia (PE) is a placental disease characterized by insufficient trophoblast cell invasion. Our clinical results revealed that serum levels of EGF were downregulated while serum and placental levels of KISS1 were upregulated in PE patients. CONCLUSIONS: This study demonstrates that downregulation of EGF can lead to poor trophoblast cell invasion by increasing KISS1 expression which subsequently contributes to the pathogenesis of PE. Video Abstract.

Association between human SHBG gene polymorphisms and risk of PCOS: a meta-analysis.

Sex hormone-binding globulin (SHBG) is a plasma glycoprotein that binds androgens and oestrogens, and regulates their bioavailability to target tissues. To date, several human SHBG gene polymorphisms have been identified. Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders, and hyperandrogenism has been considered to be a hallmark of PCOS. Many studies have examined the association between SHBG gene polymorphisms and PCOS risk, but the results have been inconclusive or inconsistent. Therefore, the aim of this meta-analysis was to investigate whether SHBG gene polymorphisms are associated with risk of PCOS. Twelve studies were included, involving 4733 participants: 2271 patients with PCOS and 2462 control participants. The results revealed that SHBG polymorphism of eight or more (TAAAA)n pentanucleotide repeats (rs35785886) was associated with PCOS risk (odds ratio [OR] = 1.24, 95% confidence interval [CI] = 1.06, 1.44, Z = 2.77, P = 0.006) and low serum SHBG concentrations in women with PCOS (standardized mean difference = -0.83, 95% CI = -1.54, -0.12, Z = 2.30, P = 0.02). Other SHBG gene polymorphisms (rs6259, rs6257, rs727428 and rs1799941) were not significantly associated with either PCOS risk or serum SHBG concentrations. These findings suggest that the presence of a polymorphism of eight or more SHBG (TAAAA)n may be a predictive factor for the risk of PCOS.

Ambient air pollutant exposure and in vitro fertilization treatment outcomes in Zhengzhou, China.

OBJECTIVE: To study the association between ambient air pollutant exposure during the follicular phase and in vitro fertilization (IVF) outcomes. DESIGN: A single-center retrospective analysis. SETTING: Henan Province, China. PATIENTS: Patients (n = 6659) living in Zhengzhou, Henan Province in central China who underwent their first IVF cycle at the First Affiliated Hospital of Zhengzhou University between 2013 and 2019 were included for analysis. INTERVENTION: None. MAIN OUTCOME MEASURE: The relationships between PM2.5, PM10, and AQI (Air Quality Index) with IVF outcomes during the follicular phase (period I, 85 days before oocyte retrieval; period II, gonadotrophin start to oocyte retrieval). RESULTS: Compared with the bottom tertile, exposure to the top PM2.5 and PM10 tertiles during period I was associated with decreased clinical pregnancy (PM2.5: adjusted odds ratio [OR], 0.838%, and 95% confidence interval [CI], 0.723 and 0.971; PM10: adjusted OR, 0.818%, and 95% CI, 0.705 and 0.950), and decreased live birth rate (PM2.5: adjusted odds ratio [OR], 0.852%, and 95% confidence interval [CI], 0.736 and 0.987; PM10: adjusted OR, 0.850%, and 95% CI, 0.733 and 0.986), and exposure to the top PM2.5 tertile during period II adversely affected clinical pregnancy and the live birth rate (adjusted OR, 0.824%, and 95% CI, 0.711 and 0.955; adjusted OR, 0.817%, and 95% CI, 0.706 and 0.945). Compared with the bottom PM10 tertile, exposure to the middle PM10 tertile in period II showed decreased clinical pregnancies and live births (adjusted OR, 0.844; 95% CI, 0.729 and 0.978, adjusted OR, 0.846; 95% CI, 0.731 and 0.979). The PM10 level during period II of the follicular phase tend to adversely affect live birth rate, but the tendency did not reach significance (P = 0.051). CONCLUSION: Exposure to PM2.5 and PM10 before oocyte retrieval has an adverse effect on IVF outcomes. CAPSULE: Exposure to PM2.5 and PM10 before oocyte retrieval has an adverse effect on IVF outcomes.

High GDF-8 in follicular fluid is associated with a low pregnancy rate in IVF patients with PCOS.

Polycystic ovary syndrome (PCOS) is the most common cause of female infertility. Growth differentiation factor-8 (GDF-8) is expressed in the ovary and can be detected in human follicular fluid which provides an important microenvironment for maintaining physiological functions of the ovarian follicle. To date, the relationship between GDF-8 levels in follicular fluid and the risk of PCOS is completely unknown. In the present study, we show that during the process of the controlled ovarian hyperstimulation (COH), serum GDF-8 levels are higher on the day of gonadotropin administration and 14 days after embryo transfer in in vitro fertilization (IVF) patients with PCOS than they are in IVF patients without PCOS. Importantly, GDF-8 levels in follicular fluid at oocyte retrieval are also higher in PCOS patients than in non-PCOS patients. Treatment of primary human granulosa-lutein (hGL) cells with GDF-8 downregulates StAR protein expression and the inhibition is more pronounced in hGL cells from PCOS patients than it is in cells from non-PCOS patients. Importantly, high GDF-8 levels and low progesterone (P4) levels were associated with poor pregnancy outcomes in PCOS patients. Our results provide the first evidence that aberrant expression of GDF-8 in the follicular fluid of PCOS patients results in abnormal P4 expression, which leads to poor pregnancy outcomes.

Factors related to early spontaneous miscarriage during IVF/ICSI treatment: an analysis of 21,485 clinical pregnancies.

RESEARCH QUESTION: Which factors are related to early spontaneous miscarriage in IVF-conceived clinical pregnancies? DESIGN: A total of 21,485 clinical pregnancies were included in the analysis. First, early spontaneous miscarriage rates were compared among different groups according to female age, body mass index (BMI), number of previous miscarriages, infertility diagnosis and type and cycle characteristics. Then, the spontaneous miscarriage rate in patients with polycystic ovary syndrome (PCOS), uterus malformation and endometriosis was compared with that in patients with male factor infertility alone. Last, logistic regression was used to analyse factors affecting the early spontaneous miscarriage rate. RESULTS: Of the 21,485 cycles, 2703 cycles (12.58%) resulted in early spontaneous miscarriage. In patients <35 years old, those with uterus malformation or PCOS experienced significantly higher spontaneous miscarriage rates (14.44% versus 9.47%, P = 0.027; 11.43% versus 9.47%; P = 0.003) compared with controls (male factor only). In multivariate logistic regression analysis, the spontaneous miscarriage rate increased in frozen embryo transfer cycles in patients <35 years old (odds ratio [OR] 1.449, 95% confidence interval [CI] 1.303-1.611, P = 0.000), but decreased in patients ≥35 years old (OR 0.794, 95% CI 0.671-0.939, P = 0.007) compared with fresh cycles. CONCLUSIONS: Female age, number of previous miscarriages and endometrial thickness on the day of embryo transfer were independent factors associated with early spontaneous miscarriage. PCOS, uterus malformation and frozen embryo transfer significantly increased spontaneous miscarriage rate in patients <35 years old compared with male factor alone controls. However, frozen embryo transfer decreased the spontaneous miscarriage rate in patients ≥35 years old compared with fresh cycles.

Association between vascular endothelial growth factor gene polymorphisms and PCOS risk: a meta-analysis.

Vascular endothelial growth factor (VEGF) plays important roles in the pathogenesis of polycystic ovary syndrome (PCOS). Several single nucleotide polymorphisms (SNP) of the VEGF gene have been identified and are associated with the aberrant secretion of VEGF protein. This meta-analysis aimed to evaluate the impact of the VEGF +405G>C (rs2010963), -460C>T (rs833061) and -2578A>C (rs699947) polymorphisms on PCOS susceptibility. A systematic search of the Embase, PubMed, Web of Science and Wanfang databases was carried out to identify relevant studies published before 19 July 2019. Seven eligible studies were included in this meta-analysis involving 1100 patients with PCOS and 1141 control individuals. The pooled analysis revealed no significant association between PCOS risk and the +405G>C (rs2010963), -460C>T (rs833061) or -2578A>C (rs699947) polymorphisms in women. Subgroup analysis by ethnicity indicated that Asian women carrying the VEGF +405C allele had a lower risk of PCOS (C versus G: odds ratio [OR] 0.731, 95% confidence interval [CI] 0.544-0.982, P < 0.05, I2 = 46.4%; CG versus GG: OR 0.667, 95% CI 0.469-0.948, P < 0.05, I2 = 18.4%; CC versus GG: OR 0.611, 95% CI 0.390-0.958, P < 0.05, I2 = 24.3%). The study demonstrates that for all women regardless of ethnicity, no significant associations between VEGF SNP and PCOS were observed; however, +405G>C (rs2010963) may protect Asian women from PCOS.

Upregulation of AREG, EGFR, and HER2 contributes to increased VEGF expression in granulosa cells of patients with OHSS†.

Ovarian hyperstimulation syndrome (OHSS) is a serious iatrogenic complication in women undergoing induction of ovulation with human chorionic gonadotropin (hCG) for assisted reproductive techniques. Amphiregulin (AREG) is the most abundant epidermal growth factor receptor (EGFR) ligand expressed in human granulosa cells and follicular fluid and can be upregulated by luteinizing hormone (LH)/hCG. However, whether the expression levels of AREG, EGFR, and HER2 change in the granulosa cells of OHSS patients remains unknown. If it does, whether these molecules are involved in the development of OHSS requires investigation. In the present study, we showed that AREG, EGFR, and HER2 transcripts in granulosa cells as well as follicular fluid AREG proteins were elevated in OHSS patients. Increased AREG levels were associated with transcript levels and follicular content of vascular endothelial growth factor (VEGF), the marker for OHSS pathology. Treatment of cultured granulosa cells with AREG stimulated VEGF expression and secretion, with granulosa cells from OHSS patients showing more rapid and pronounced increases than the non-OHSS group. In addition, siRNA-mediated knockdown of EGFR and AREG attenuated the hCG-induced upregulation of VEGF. This study demonstrated that granulosa cell-secreted AREG plays an important role in the development of OHSS, suggesting that the EGFR/HER2-mediated signaling could be a novel drug target for the prevention and treatment of OHSS.