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Τhis study aims to investigate whether the addition of low-dose hCG throughout stimulation in infertile women undergoing IVF improves IVF outcome parameters. This is a prospective, multicenter, randomized, double-blind, placebo-controlled, Phase IIIb clinical study, conducted in three university IVF units. We studied whether the addition of 100 IU hCG/day to a short GnRH agonist IVF protocol from the onset of the follicular phase (group 1, n=40) or placebo (group 2, n=41) had any impact on the number of high-quality transferred embryos at day 2 and clinical pregnancy rates. The comparison encompassed descriptive statistics, and univariate and multivariate analyses. Concerning the primary outcomes, we found no differences in both the number of high-quality embryos (≥2) at day 3 [21/40 (52.5%) vs. 14/41 (34.2%), p=0.095] and clinical pregnancy rates [10/40 (25%) vs. 10/41 (24.4%), p=0.949], respectively. Similarly, there were no differences concerning the secondary outcomes preset for this trial. According to the results of the multivariate logistic regression analysis, no significant associations were noted for primary outcomes (clinical pregnancy: adjusted OR=0.89, 95% CI: 0.29-2.75; (≥2 excellent quality embryos at day 3: adjusted OR=0.54, 95% CI: 0.21-1.42, with group 1 set as reference category); similarly, no differences were noted with respect to secondary outcomes, except from the increased odds of ≥2 poor-quality embryos at day 3 occurring in group 2 (adjusted OR= 11.69, 95%CI: 1.29-106.19). The addition of low-dose hCG to a short GnRH agonist protocol for IVF does not improve the number of top-quality embryos and clinical pregnancy rates.

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Since the birth of Louise Brown, in vitro fertilization (IVF) stimulation protocols have evolved significantly. One particular area of focus has been the process of final oocyte maturation, during which the oocyte gains competence to support fertilization and early embryonic development up to implantation. The field of human assisted reproductive technology (ART) is witnessing increased utilization of GnRH agonists (GnRHa) as trigger agents, in addition to or instead of the traditionally used human chorionic gonadotropin (hCG). Future translational studies will reveal whether oocyte developmental competence, as reflected in live birth outcomes, are not only non-inferior, but also superior with the use of GnRHa as a trigger for both nuclear and cytoplasmic oocyte maturation.

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Low-molecular-weight agonists of luteinizing hormone (LH)/human chorionic gonadotropin (hCG) receptor (LHCGR), which interact with LHCGR transmembrane allosteric site and, in comparison with gonadotropins, more selectively activate intracellular effectors, are currently being developed. Meanwhile, their effects on testicular steroidogenesis have not been studied. The purpose of this work is to perform a comparative study of the effects of 5-amino-N-tert-butyl-4-(3-(1-methylpyrazole-4-carboxamido)phenyl)-2-(methylthio)thieno[2,3-d] pyrimidine-6-carboxamide (TP4/2), a LHCGR allosteric agonist developed by us, and hCG on adenylyl cyclase activity in rat testicular membranes, testosterone levels, testicular steroidogenesis and spermatogenesis in young (four-month-old), aging (18-month-old) and diabetic male Wistar rats. Type 1 diabetes was caused by a single streptozotocin (50 mg/kg) injection. TP4/2 (20 mg/kg/day) and hCG (20 IU/rat/day) were administered for 5 days. TP4/2 was less effective in adenylyl cyclase stimulation and ability to activate steroidogenesis when administered once into rats. On the 3rd-5th day, TP4/2 and hCG steroidogenic effects in young adult, aging and diabetic rats were comparable. Unlike hCG, TP4/2 did not inhibit LHCGR gene expression and did not hyperstimulate the testicular steroidogenesis system, moderately increasing steroidogenic proteins gene expression and testosterone production. In aging and diabetic testes, TP4/2 improved spermatogenesis. Thus, during five-day administration, TP4/2 steadily stimulates testicular steroidogenesis, and can be used to prevent androgen deficiency in aging and diabetes.

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PURPOSE: To compare morphokinetic parameters and quality of embryos derived from GnRH antagonist ICSI cycles triggered either with GnRH agonist or standard hCG between matched groups of patients. METHODS: Morphokinetic parameters of embryos derived from matched first GnRH antagonist ICSI cycles triggered by GnRH agonist or standard hCG between 2013 and 2016 were compared. Matching was performed for maternal age, peak estradiol levels, and number of oocytes retrieved. Outcome measures were: time to pronucleus fading (tPNf), cleavage timings (t2-t8), synchrony of the second and third cycles (S2 and S3), duration of the second and third cycle (CC2 and CC3), optimal cell cycle division parameters, and known implantation data (KID) scoring for embryo quality. Multivariate linear and logistic regression analyses were performed for confounding factors. RESULTS: We analyzed 824 embryos from 84 GnRH agonist trigger cycles and 746 embryos from 84 matched hCG trigger cycles. Embryos derived from the cycles triggered with hCG triggering cleaved faster than those deriving from GnRH agonist trigger. The differences were significant throughout most stages of embryo development (t3-t6), and a shorter second cell cycle duration of the hCG trigger embryos was observed. There was no difference in synchrony of the second and third cell cycles and the optimal cell cycle division parameters between the two groups, but there was a higher percentage of embryos without multinucleation in the hCG trigger group (27.8% vs. 21.6%, p < 0.001). CONCLUSION: The type of trigger in matched antagonist ICSI cycles was found to affect early embryo cleavage times but not embryo quality.

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PURPOSE: Recent experimental evidence on non-mammalian animal models showed that D-Aspartic acid (d-Asp) administration increases testosterone levels through upregulation of StAR in Leydig cells. In this study, we aimed to investigate in vitro the signaling pathway associated with d-Asp stimulation in MA-10 murine Leydig cells. METHODS: MA-10 cells were stimulated with different concentrations of d-Asp, in presence or absence of hCG. Then total testosterone (T) levels in the culture medium were evaluated by electrochemiluminescence immunoassay, and StAR and LHR protein expressions were quantified by the means of Western blotting. LHR cellular localization after hormonal stimulation was assessed by immunofluorescence. RESULTS: Stimulation with the sole d-Asp did not induce any relevant increase of T release from cultured cells. On the other hand, stimulation with hCG induced significant increase of T (P = 0.045). Concomitant stimulation with hCG and d-Asp, at the concentration of 0.1 and 1 nM, induced additional and significant increase of released T (P = 0.03 and P = 0.04, respectively). StAR protein levels increased after concomitant stimulation with hCG and d-Asp 0.1 nM, compared with stimulation with the sole hCG (P = 0.02), whereas no variation in LHR protein expression was observed. Finally, d-Asp attenuated displacement of LHR staining, from cell membrane to cytoplasm, subsequent to hCG stimulation. CONCLUSIONS: In this study, we confirmed a steroidogenic role for d-Asp, in concert with hCG, on murine Leydig cells, which is mediated by an increase in StAR protein levels. In addition, we showed that the possible mechanism subtending the effect of d-Asp could rely on the modulation of LHR exposure on the cell membrane.

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STUDY QUESTION: Is the drug used for final oocyte maturation a factor in determining the prevalence of empty follicle syndrome (EFS)? SUMMARY ANSWER: The drug used for final oocyte maturation is not a factor in determining the prevalence of EFS among women unaffected by infertility. WHAT IS KNOWN ALREADY: Despite satisfactory follicular stimulation and adequate follicular development, cases of EFS, i.e. failure to recover any cumulus oocyte complex, have been reported both with hCG and GnRH agonist triggering. No standard management protocol has been proposed so far. STUDY DESIGN, SIZE, DURATION: Retrospective analysis of oocyte donation cycles performed between August 2006 and April 2013 in a large private fertility centre. PARTICIPANTS/MATERIALS, SETTING, METHODS: The analysis included 12 483 oocyte donation cycles of which 74 were EFS cycles. All cycles were triggered with either hCG or GnRH agonists. MAIN RESULTS AND THE ROLE OF CHANCE: There were no differences in the gonadotropic stimulation, pituitary suppression and triggering drug between cycles where oocytes were recovered successfully and EFS cycles. The total prevalence of EFS was 0.59%. Given the rarity of the syndrome, caution is advised when interpreting the analysis. LIMITATIONS, REASONS FOR CAUTION: The main limitation of this study is its retrospective nature. Although this is the largest analysis of EFS in donors reported so far, its statistical power is limited because the syndrome has a low incidence. In some cycles of EFS from 2006 to 2007 there is a lack of hormone data. WIDER IMPLICATIONS OF THE FINDINGS: Our findings may be generalized to oocyte donors and IVF patients younger than 35 years old, with cycles undergoing final maturation triggering with either hCG or GnRH agonists. The generalization cannot be extended to patients with an ovarian factor as the cause of their reproductive pathology. The theoretical aetiology of a temporary hypothalamic-pituitary hyposensitivity can explain the cycles where a rescue protocol with hCG has been successful. STUDY FUNDING/COMPETING INTERESTS: This work was supported in part by funding from Fundaciò EUGIN. The authors have no conflicts to declare. TRIAL REGISTRATION NUMBER: NA.

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OBJECTIVE: To investigate the correlation between the estradiol (E2) level change after hCG administration and the live birth rate in GnRH agonist long or short protocols, and to explore the possible factors related to E2 dynamics after hCG administration during controlled ovarian hyperstimulation (COH). STUDY DESIGN: A retrospective analysis was performed on 2868 patients who received IVF/intracytoplasmic sperm injection (ICSI) treatment with GnRH agonist long or short protocol. The patients were divided into three groups according to their serum E2 changes after hCG administration, and the live birth rates were compared among groups. The area under the receiver operating characteristic (ROC) curve was calculated to assess the predictive value of E2 change for the probability of live birth. Logistic regression analysis was also applied to exclude interference from various confounding factors. Finally, multivariate regression analysis was conducted to assess factors related to the E2 change after hCG administration. RESULTS: No significant difference was observed in live birth rates (4.26%, 36.38% or 30.81% in long protocol (P=0.697); 25.81%, 26.71% or 30.81% in short protocol (P=0.697)) among patients with increasing, plateauing or decreasing E2 responses after hCG administration. The area under the ROC curve for the E2 change in prediction of live birth rate was 0.506 in long protocol, or 0.524 in short protocol. Logistic regression analysis showed that the serum E2 change after hCG administration had no correlation with live birth rate. Multivariate regression analysis showed that the percentage of mature follicles (larger than 14mm) and the duration of stimulation negatively correlated with the E2 change after hCG administration. CONCLUSIONS: In GnRH agonist cycles, the serum E2 change after hCG administration had no correlation with live birth rate in fresh embryo transfer cycles, and this change negatively correlated with the percentage of mature follicles on the day of hCG administration.

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OBJECTIVE: To compare fertilization, implantation and pregnancy rates in donor oocyte cycles triggered for final oocyte maturation with either human chorionic gonadotropin (hCG) or gonadotropin releasing hormone (GnRH) agonist in the same donor population in two sequential stimulation cycles. DESIGN: Prospective randomized cross-over trial. SETTING: Private infertility clinic. PATIENT(S): Eighty-eight stimulation cycles in 44 egg donors. INTERVENTIONS: Controlled ovarian hyperstimulation (COH) with GnRH antagonist protocol triggered with hCG or GnRH agonist (leuprolide acetate 0.15 mg) in the same egg donors in two consecutive cycles. MAIN OUTCOME MEASURE(S): The primary outcome measure was the proportion of mature and fertilized oocytes per donor cycle. Secondary outcome measures were implantation and pregnancy rates in the recipients and incidence of ovarian hyperstimulation syndrome (OHSS) in oocyte donors. RESULT(S): The proportion of mature oocytes, fertilized oocytes and mean embryo scores were comparable between the two triggering agents. While implantation (36.53% vs, 32.93%), pregnancy (69.08% vs. 68.81%) and clinical pregnancy (41.3% vs. 40.2%) rates were comparable for the groups, the incidence of OHSS was significantly lower in GnRH than in hCG triggered cycles. CONCLUSION(S): Fertilization, implantation and pregnancy rates from donor oocytes stimulated with GnRH antagonist protocol were identical for donor cycles triggered with hCG and GnRH agonist. GnRH antagonist triggering in egg donors was associated with lower rates of OHSS.

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Despite the fact that many methods have been proposed for the management of severe ovarian hyperstimulation syndrome (OHSS), its prevention is mainly achieved by withholding human chorionic gonadotrophin (HCG) administration and cycle cancellation. Currently no curative therapy is available. Three women diagnosed with polycystic ovarian syndrome underwent ovarian stimulation for IVF using a long gonadotrophin-releasing hormone (GnRH) agonist protocol. Six days after oocyte retrieval, severe early OHSS was diagnosed by analysis of haematocrit, white blood cell (WBC) count, serum urea, and ultrasonographic assessment of ovarian size and ascitic fluid. On the same day, antagonist administration was administrated and continued daily for 1 week, while resulting blastocysts were cryopreserved. Progression of severe early OHSS was inhibited in all three patients. A marked decrease of haematocrit, WBC, ascitic fluid, oestradiol, progesterone and ovarian volume was observed, during 1 week of follow-up suggesting a luteolytic effect of GnRH antagonist. None of the patients required hospitalization. In conclusion, GnRH antagonist administration combined with blastocyst cryopreservation 6 days post retrieval might represent a new approach for the effective management of patients with established severe OHSS. The flexibility of the approach allows the elongation of the monitoring period up to 8 days following HCG administration.

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In this retrospective study of 74 oocyte-donor IVF cycles, the rates of fertilization, implantation, clinical pregnancy, ongoing pregnancy, and early pregnancy loss were similar after an agonist or hCG trigger. These findings suggest that the agonist trigger is a viable alternative for oocyte donors with significant risk factors for ovarian hyperstimulation syndrome.

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The substituted thieno[2,3-d]pyrimidine 3 (Org 41841), a partial agonist for the luteinizing hormone/choriogonadotropin receptor (LHCGR) and the closely related thyroid-stimulating hormone receptor (TSHR), was fundamentally altered, and the resulting analogues were analyzed for their potencies, efficacies, and specificities at LHCGR and TSHR. Chemical modification of the parent compound combined with prior mutagenesis of TSHR provided compelling experimental evidence in support of computational models of 3 binding to TSHR and LHCGR within their transmembrane cores. Biochemical analysis of a specific modification to the chemical structure of 3 provides additional evidence of a H-bond between the ligand and a glutamate residue in transmembrane helix 3, which is conserved in both receptors. Several key interactions were surveyed to determine their respective biochemical roles in terms of both van der Waals dimensions and hydrogen bond capacity and the respective relationship to biological activity.

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BACKGROUND: We aimed to examine the serum levels of inhibin A, vascular endothelial growth factor (VEGF), tumour necrosis factor alpha (TNFalpha), estradiol (E2) and progesterone levels after triggering of final oocyte maturation with GnRH agonist compared with HCG in patients with polycystic ovaries (PCO) and to investigate the relationship between these markers and ovarian hyperstimulation syndrome (OHSS). METHODS: Twenty-eight patients with PCO, undergoing controlled ovarian hyperstimulation with FSH and GnRH antagonist for IVF-embryo transfer treatment, were randomized for triggering of final oocyte maturation with GnRH agonist (GnRH agonist group, n = 15) or HCG (HCG group, n = 13). Blood samples were obtained on the day of randomization and thereafter every 2-7 days. Serum levels of inhibin A, VEGF, TNFalpha, E2 and progesterone, the incidence of OHSS, ovarian size and pelvic fluid accumulation were evaluated. RESULTS: Serum inhibin A, E2 and progesterone levels were significantly lower in the GnRH agonist group compared with the HCG group, particularly on the day of embryo transfer (P < 0.0001). Serum VEGF and TNFalpha levels were similar between the two groups. Four patients in the HCG group developed severe OHSS, whereas no patient had any symptoms or signs of OHSS in the GnRH-agonist group (P < 0.05). CONCLUSIONS: In patients with PCO treated with FSH/GnRH antagonist, final oocyte maturation with GnRH agonist instead of HCG reduces significantly inhibin A, E2 and progesterone levels during the luteal phase. This phenomenon reflects the inhibition of the corpus luteum function and may explain, at least in part, the mechanism of OHSS prevention in high-risk patients. Our results do not support a crucial role for VEGF or TNFalpha in OHSS.

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Highly purified human chorionic gonadotropin (hCG) interacts with the thyrotropin (TSH) receptor and stimulates triiodothyronine (T3) secretion, iodide uptake and organification, and cyclic adenosine monophosphate (cAMP) formation in human thyroid follicles. Because of interest in the role of the carbohydrate component in the structure-function relationships of hCG we undertook to deplete hCG of its sialic acid or carbohydrate residues and assess the thyrotropic activity of the carbohydrate-modified forms. For this purpose, we used our assay system consisting of human thyroid follicles cultured and suspended in collagen gel in serum-free medium. Under these conditions, the cells are organized as follicular three-dimensional structures with normal polarity, enabling enhanced responsiveness to hormonal stimulation, and T3 secretion can be measured as a response parameter. Desialylated (ds)-hCG and deglycosylated (dg)-hCG dose-dependently stimulated T3 secretion, iodide uptake and organification, and in each case did so with about twice the intrinsic activity of native hCG. Indeed, removal of the sialic acid or carbohydrate residues from native hCG transformed it into a thyroid stimulator that elicited a maximal response in terms of iodide uptake, organification and T3 secretion by human thyroid follicles as high as TSH and almost twice as high as native hCG. Not only were ds-hCG and dg-hCG more intrinsically active than hCG, they were more than five times as potent. As with hCG, both ds-hCG and dg-hCG managed to elicit such responses in human thyrocytes while evoking minimal amounts of cAMP, illustrating the concept of cAMP superfluity and highlighting the potential pitfalls of using cAMP as a measure of hormonal bioactivity. hCG, and to a greater extent ds-hCG and dg-hCG, inhibited, as did TSH, gamma-interferon-induced human leukocyte antigen-DR (HLA-DR) expression in human thyrocytes, again reflecting the intrinsic thyrotropic activity of native hCG and its variants depleted of sialic acid or carbohydrate residues. In conclusion, this is the first report on the thyrotropic activity of ds-hCG and dg-hCG using the physiologically relevant hormonal end-point response, thyroid hormone secretion. The study was conducted in a serum-free culture system of human thyroid follicles and shows that removal of the sialic acid or carbohydrate residues from native hCG transform hCG variants into thyroid stimulating superagonists. The hCG variants inhibited, as did TSH, gamma-interferon-induced HLA-DR expression.

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