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Abstract
Gonadotropins are glycoprotein sex hormones regulating development and reproduction and bind to specific G protein–coupled receptors expressed in the gonads. Their effects on multiple signaling cascades and intracellular events have recently been characterized using novel technological and scientific tools. The impact of allosteric modulators on gonadotropin signaling, the role of sugars linked to the hormone backbone, the detection of endosomal compartments supporting signaling modules, and the dissection of different effects mediated by these molecules are areas that have advanced significantly in the last decade. The classic view providing the exclusive activation of the cAMP/protein kinase A (PKA) and the steroidogenic pathway by these hormones has been expanded with the addition of novel signaling cascades as determined by high-resolution imaging techniques. These new findings provided new potential therapeutic applications. Despite these improvements, unanswered issues of gonadotropin physiology, such as the intrinsic pro-apoptotic potential to these hormones, the existence of receptors assembled as heteromers, and their expression in extragonadal tissues, remain to be studied. Elucidating these issues is a challenge for future research.
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Affiliation(s)
- Livio Casarini
- Unit of Endocrinology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Via G. Campi 287, 41125 Modena, Italy
- Center for Genomic Research, University of Modena and Reggio Emilia, Via G. Campi 287, 41125 Modena, Italy
| | - Manuela Simoni
- Unit of Endocrinology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Via G. Campi 287, 41125 Modena, Italy
- Center for Genomic Research, University of Modena and Reggio Emilia, Via G. Campi 287, 41125 Modena, Italy
- Unit of Endocrinology, Department of Medical Specialties, Azienda Ospedaliero-Universitaria di Modena, Via P. Giardini 1355, 41126 Modena, Italy
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Brady PC, Farland LV, Racowsky C, Ginsburg ES. Hyperglycosylated human chorionic gonadotropin as a predictor of ongoing pregnancy. Am J Obstet Gynecol 2020; 222:68.e1-68.e12. [PMID: 31401260 DOI: 10.1016/j.ajog.2019.08.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 07/14/2019] [Accepted: 08/05/2019] [Indexed: 11/16/2022]
Abstract
BACKGROUND Hyperglycosylated human chorionic gonadotropin, the predominant human chorionic gonadotropin variant secreted following implantation, is associated with trophoblast invasion. OBJECTIVE To determine whether the initial serum hyperglycosylated human chorionic gonadotropin differs between ongoing and failed pregnancies, and to compare it to total serum human chorionic gonadotropin as a predictor of ongoing pregnancy. MATERIALS AND METHODS Women undergoing fresh/frozen in vitro fertilization cycles at a university-based infertility clinic with an autologous day 5 single embryo transfer resulting in serum human chorionic gonadotropin >3 mIU/mL (n = 115) were included. Human chorionic gonadotropin was measured 11 days after embryo transfer in a single laboratory (coefficient of variation <6%). Surplus frozen serum (-80oC) was shipped to Quest Laboratories for measurement of hyperglycosylated human chorionic gonadotropin (coefficient of variation <9.1%). Linear regression analyses adjusted for oocyte age a priori were used to compare human chorionic gonadotropin and hyperglycosylated human chorionic gonadotropin in ongoing pregnancies (>8 weeks of gestation) and failed pregnancies (clinical pregnancy loss, biochemical and ectopic pregnancies). RESULTS A total of 85 pregnancies (73.9%) were ongoing. Hyperglycosylated human chorionic gonadotropin and human chorionic gonadotropin values were highly correlated (Pearson correlation coefficient 92.14, P < .0001), and mean values of both were positively correlated with blastocyst expansion score (P value test for trend < .0004). Mean human chorionic gonadotropin and hyperglycosylated human chorionic gonadotropin were significantly higher in ongoing vs failed pregnancies. Among ongoing pregnancies vs clinical losses, mean hyperglycosylated human chorionic gonadotropin, but not human chorionic gonadotropin, was significantly higher (19.0 vs 12.2 ng/mL, β -8.1, 95% confidence interval -13.0 to -3.2), and hyperglycosylated human chorionic gonadotropin comprised a higher proportion of total human chorionic gonadotropin (4.6% vs 4.1%; risk ratio, 0.79; 95% confidence interval, 0.66-0.94). CONCLUSION Measured 11 days after single blastocyst transfer, hyperglycosylated human chorionic gonadotropin and human chorionic gonadotropin values were highly correlated, but only mean hyperglycosylated human chorionic gonadotropin and its ratio to total human chorionic gonadotropin were significantly higher in ongoing pregnancies vs clinical pregnancy losses. Further evaluation of hyperglycosylated human chorionic gonadotropin, including in multiple embryo transfers and multiple pregnancy, and using serial measurements, is required.
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Affiliation(s)
- Paula C Brady
- Department of Obstetrics and Gynecology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA.
| | - Leslie V Farland
- Department of Obstetrics and Gynecology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA
| | - Catherine Racowsky
- Department of Obstetrics and Gynecology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA
| | - Elizabeth S Ginsburg
- Department of Obstetrics and Gynecology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA
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Koistinen H, Koel M, Peters M, Rinken A, Lundin K, Tuuri T, Tapanainen JS, Alfthan H, Salumets A, Stenman UH, Lavogina D. Hyperglycosylated hCG activates LH/hCG-receptor with lower activity than hCG. Mol Cell Endocrinol 2019; 479:103-109. [PMID: 30287399 DOI: 10.1016/j.mce.2018.09.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 08/13/2018] [Accepted: 09/22/2018] [Indexed: 01/15/2023]
Abstract
While human chorionic gonadotropin (hCG) appears to have an essential role in early pregnancy, it is controversial whether the hyperglycosylated form of hCG (hCG-h), which is the major hCG isoform during the first 4-5 weeks of pregnancy, is able to activate LH/hCG receptor (LHCGR). To address this, we utilized different extensively characterized hCG and hCGβ reference reagents, cell culture- and urine-derived hCG-h preparations, and an in vitro reporter system for LHCGR activation. The WHO hCG reference reagent (99/688) was found to activate LHCGR with an EC50-value of 3.3 ± 0.6 pmol/L (n = 9). All three studied hCG-h preparations were also able to activate LHCGR, but with a lower potency (EC50-values between 7.1 ± 0.5 and 14 ± 3 pmol/L, n = 5-11, for all P < 0.05 as compared to the hCG reference). The activities of commercial urinary hCG (Pregnyl) and recombinant hCG (Ovitrelle) preparations were intermediate between those of the hCG reference and the hCG-h. These results strongly suggest that the hCG-h is functionally similar to hCG, although it has lower potency for LHCGR activation. Whether this explains the reduced proportion of hCG-h to hCG reported in patients developing early onset pre-eclampsia or those having early pregnancy loss remains to be determined.
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Affiliation(s)
- Hannu Koistinen
- Department of Clinical Chemistry, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
| | - Mariann Koel
- Competence Centre on Health Technologies, Tartu, Estonia; Department of Cell Biology, Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
| | - Maire Peters
- Competence Centre on Health Technologies, Tartu, Estonia; Department of Obstetrics and Gynaecology, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Ago Rinken
- Institute of Chemistry, University of Tartu, Tartu, Estonia
| | - Karolina Lundin
- Department of Obstetrics and Gynecology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Timo Tuuri
- Department of Obstetrics and Gynecology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Juha S Tapanainen
- Department of Obstetrics and Gynecology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; Department of Obstetrics and Gynecology, University Hospital of Oulu, University of Oulu, Medical Research Center Oulu and PEDEGO Research Unit, Oulu, Finland
| | - Henrik Alfthan
- Department of Clinical Chemistry, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Andres Salumets
- Competence Centre on Health Technologies, Tartu, Estonia; Department of Obstetrics and Gynaecology, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia; Department of Obstetrics and Gynecology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Ulf-Håkan Stenman
- Department of Clinical Chemistry, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Darja Lavogina
- Competence Centre on Health Technologies, Tartu, Estonia; Institute of Chemistry, University of Tartu, Tartu, Estonia
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Makrigiannakis A, Vrekoussis T, Zoumakis E, Kalantaridou SN, Jeschke U. The Role of HCG in Implantation: A Mini-Review of Molecular and Clinical Evidence. Int J Mol Sci 2017. [PMID: 28629172 PMCID: PMC5486126 DOI: 10.3390/ijms18061305] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Embryo implantation is a complex process involving continuous molecular cross-talk between the embryo and the decidua. One of the key molecules during this process is human chorionic gonadotropin (HCG). HCG effectively modulates several metabolic pathways within the decidua contributing to endometrial receptivity. Herein, a brief overview of the molecular mechanisms regulated by HCG is presented. Furthermore, we summarize the existing evidence regarding the clinical impact on reproductive outcomes after endometrial priming with HCG prior to embryo transfer. Although promising, further evidence is needed to clarify the protocol that would lead to beneficial outcomes.
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Affiliation(s)
- Antonis Makrigiannakis
- Department of Obstetrics and Gynecology, Medical School, University of Crete, Heraklion 71003, Greece.
| | - Thomas Vrekoussis
- Department of Obstetrics and Gynecology, Medical School, University of Ioannina, Ioannina 45110, Greece.
| | - Emmanouel Zoumakis
- Department of Pediatrics, Medical School, University of Athens, Athens 11527, Greece.
| | - Sophia N Kalantaridou
- Second Department of Obstetrics and Gynecology, Medical School, University of Athens, Athens 11528, Greece.
| | - Udo Jeschke
- Departments of Obstetrics and Gynecology, Medical School, Ludwig-Maximilians University of Munich, Campus Innenstadt & Campus Grosshadern, Munich 80337, Germany.
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Casarini L, Riccetti L, De Pascali F, Nicoli A, Tagliavini S, Trenti T, La Sala GB, Simoni M. Follicle-stimulating hormone potentiates the steroidogenic activity of chorionic gonadotropin and the anti-apoptotic activity of luteinizing hormone in human granulosa-lutein cells in vitro. Mol Cell Endocrinol 2016; 422:103-114. [PMID: 26690776 DOI: 10.1016/j.mce.2015.12.008] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 12/07/2015] [Accepted: 12/08/2015] [Indexed: 01/15/2023]
Abstract
Luteinizing hormone (LH) and choriogonadotropin (hCG) are glycoprotein hormones regulating ovarian function and pregnancy, respectively. Since these molecules act on the same receptor (LHCGR), they were traditionally assumed as equivalent in assisted reproduction techniques (ART), although differences between LH and hCG were demonstrated at molecular and physiological level. In this study, we demonstrated for the first time that co-treatment with a follicle-stimulating hormone (FSH) dose in the ART therapeutic range potentiates different LH- and hCG-dependent responses in vitro, measured in terms of cAMP, phospho-CREB, -ERK1/2 and -AKT activation, gene expression, progesterone and estradiol production in human granulosa-lutein cells (hGLC). We show that in the presence of FSH, hCG biopotency is about 5-fold increased, in the presence of FSH, in terms of cAMP activation. Accordingly, CREB phosphorylation and steroid production is increased under hCG and FSH co-treatment. LH effects, evaluated as steroidogenic cAMP/PKA pathway activation, do not change in the presence of FSH, which, however, increases LH-dependent ERK1/2 and AKT, but not CREB phosphorylation, resulting in anti-apoptotic effects. The different modulatory activity of FSH on LH and hCG action in vitro corresponds to their different physiological functions, reflecting proliferative effects exerted by LH during the follicular phase and before trophoblast development, and the high steroidogenic potential of hCG requested to sustain pregnancy from the luteal phase onwards.
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Affiliation(s)
- Livio Casarini
- Unit of Endocrinology, Dept. Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy; Center for the Genomic Research, University of Modena and Reggio Emilia, Modena, Italy.
| | - Laura Riccetti
- Unit of Endocrinology, Dept. Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Francesco De Pascali
- Unit of Endocrinology, Dept. Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Alessia Nicoli
- Unit of Obstetrics and Gynecology, IRCCS-Arcispedale Santa Maria Nuova, Reggio Emilia, Italy
| | | | | | - Giovanni Battista La Sala
- Unit of Obstetrics and Gynecology, IRCCS-Arcispedale Santa Maria Nuova, Reggio Emilia, Italy; Dept. of Medical and Surgical Sciences for Children and Adults, University of Modena and Reggio Emilia, Reggio Emilia, Italy
| | - Manuela Simoni
- Unit of Endocrinology, Dept. Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy; Center for the Genomic Research, University of Modena and Reggio Emilia, Modena, Italy; Dept. of Medicine, Endocrinology, Metabolism and Geriatrics, Azienda USL, Modena, Italy
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Evans J. Hyperglycosylated hCG: a Unique Human Implantation and Invasion Factor. Am J Reprod Immunol 2015; 75:333-40. [DOI: 10.1111/aji.12459] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 11/06/2015] [Indexed: 12/28/2022] Open
Affiliation(s)
- Jemma Evans
- The Hudson Institute of Medical Research; Clayton Vic. Australia
- Department of Physiology; Monash University; Clayton Vic. Australia
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Nataraja SG, Yu HN, Palmer SS. Discovery and Development of Small Molecule Allosteric Modulators of Glycoprotein Hormone Receptors. Front Endocrinol (Lausanne) 2015; 6:142. [PMID: 26441832 PMCID: PMC4568768 DOI: 10.3389/fendo.2015.00142] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 08/31/2015] [Indexed: 11/30/2022] Open
Abstract
Glycoprotein hormones, follicle-stimulating hormone (FSH), luteinizing hormone (LH), and thyroid-stimulating hormone (TSH) are heterodimeric proteins with a common α-subunit and hormone-specific β-subunit. These hormones are dominant regulators of reproduction and metabolic processes. Receptors for the glycoprotein hormones belong to the family of G protein-coupled receptors. FSH receptor (FSHR) and LH receptor are primarily expressed in somatic cells in ovary and testis to promote egg and sperm production in women and men, respectively. TSH receptor is expressed in thyroid cells and regulates the secretion of T3 and T4. Glycoprotein hormones bind to the large extracellular domain of the receptor and cause a conformational change in the receptor that leads to activation of more than one intracellular signaling pathway. Several small molecules have been described to activate/inhibit glycoprotein hormone receptors through allosteric sites of the receptor. Small molecule allosteric modulators have the potential to be administered orally to patients, thus improving the convenience of treatment. It has been a challenge to develop a small molecule allosteric agonist for glycoprotein hormones that can mimic the agonistic effects of the large natural ligand to activate similar signaling pathways. However, in the past few years, there have been several promising reports describing distinct chemical series with improved potency in preclinical models. In parallel, proposal of new structural model for FSHR and in silico docking studies of small molecule ligands to glycoprotein hormone receptors provide a giant leap on the understanding of the mechanism of action of the natural ligands and new chemical entities on the receptors. This review will focus on the current status of small molecule allosteric modulators of glycoprotein hormone receptors, their effects on common signaling pathways in cells, their utility for clinical application as demonstrated in preclinical models, and use of these molecules as novel tools to dissect the molecular signaling pathways of these receptors.
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Affiliation(s)
- Selvaraj G. Nataraja
- TocopheRx Inc., Burlington, MA, USA
- *Correspondence: Selvaraj G. Nataraja, TocopheRx Inc., 15 New England Executive Park, Suite 1087, Burlington, MA 01803, USA,
| | - Henry N. Yu
- TocopheRx Inc., Burlington, MA, USA
- EMD Serono Research and Development Institute Inc., Billerica, MA, USA
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Gallego V, Vílchez MC, Peñaranda DS, Pérez L, Herráez MP, Asturiano JF, Martínez-Pastor F. Subpopulation pattern of eel spermatozoa is affected by post-activation time, hormonal treatment and the thermal regimen. Reprod Fertil Dev 2015; 27:529-43. [DOI: 10.1071/rd13198] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2013] [Accepted: 01/08/2014] [Indexed: 11/23/2022] Open
Abstract
There has been a marked reduction in natural stocks of eels (genus Anguilla) over the past 60 years, and the culture of eels is still based on the capture of very large quantities of juveniles. It is necessary to close the life cycle in captivity in order to ease the pressure on wild populations. The aims of the present study were to evaluate sperm subpopulations (through cluster analysis of computer-aided sperm analysis data) in the European eel (Anguilla anguilla) and to assess the effects of motility acquisition time after activation (i.e. at 30, 60 and 90 s), the thermal regimen (i.e. 10°C (T10) or 15°C (T15) and up to 20°C, or constant at 20°C (T20)) and hormonal treatments (i.e. human chorionic gonadotropin (hCG), recombinant (r) hCG or pregnant mare serum gonadotropin (PMSG)) on these subpopulations. In all cases, we obtained three subpopulations of spermatozoa: low velocity and linear (S1); high velocity with low linearity (S2); and high velocity and linear (S3; considered high quality). Total motility and S1 were affected by acquisition time; thus, 30 s is recommended as the standard time for motility acquisition. When eels were kept at 20°C (T20), motility data fitted quadratic models, with the highest motility and proportion of S3 between Weeks 8 and 12 after the first injection. Lower temperatures (T10, T15) delayed spermiation and the obtaining of high-quality spermatozoa (S3), but did not seem to alter the spermiation process (similar subpopulation pattern). Conversely, the hormonal treatments altered both the dynamics of the subpopulation pattern and the onset of spermiation (with PMSG delaying it). Total motility and the yield of S3 with the widely used hCG treatment varied throughout the spermiation period. However, using rhCG allowed us to obtain high-quality and constant motility for most of the study (Weeks 7–20), and the S3 yield was also higher overall (61.8 ± 1.3%; mean ± s.e.m.) and more stable over time than the other hormonal treatments (averaging 53.0 ± 1.4%). Using T20 and rhCG would be more economical and practical, allowing us to obtain a higher number of S3 spermatozoa over an extended time.
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Abstract
Luteinizing hormone (LH) and human chorionic gonadotropin (hCG) are integral components of the hypothalamic-pituitary-gonadal axis, which controls sexual maturation and functionality. In the absence of signaling through their shared receptor, fetal sexual differentiation and post-natal development cannot proceed normally. Although they share a high degree of homology, the physiologic roles of these hormones are unique, governed by differences in expression pattern, biopotency and regulation. Whereas LH is a key regulator of gonadal steroidogenesis and ovulation, hCG is predominantly active in pregnancy and fetal development. Emerging evidence has revealed endogenous functions not previously ascribed to hCG, including participation in ovulation and fertilization, implantation, placentation and other activities in support of successful pregnancy. Spontaneous and induced mutations in LH, hCG and their mutual receptor have contributed substantially to our understanding of reproductive development and function. The lack of naturally occurring, functionally significant mutations in the β-subunit of hCG reinforce its putative role in establishment of pregnancy. Rescue of reproductive abnormalities resulting from aberrant gonadotropin signaling is possible in certain clinical contexts, depending on the nature of the underlying defect. By understanding the physiologic roles of LH and hCG in normal and pathologic states, we may better harness their diagnostic, prognostic and therapeutic potential.
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Affiliation(s)
- Janet Choi
- Department of Obstetrics and Gynecology, The Center for Women’s Reproductive Care at Columbia UniversityNew York, NYUSA
| | - Johan Smitz
- Department of Clinical Chemistry and Radioimmunology, UZ Brussel, Vrije Universiteit BrusselBrusselsBelgium
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Sonntag B, Loebbecke KC, Nofer JR, Kiesel L, Greb RR. Serum estradiol and progesterone in the mid-luteal phase predict clinical pregnancy outcome in IVF/ICSI cycles. Gynecol Endocrinol 2013; 29:700-3. [PMID: 23772781 DOI: 10.3109/09513590.2013.797392] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In this prospective study, we tested the hypothesis if E2 and P serum levels significantly differ during the luteal phase following in vitro-fertilization/intracytoplasmic sperm injection (IVF/ICSI) therapy in conception (CC) versus non-conception (NC) cycles, and their potential in the prediction of pregnancy at the earliest point in time. Serum was sampled from the day of embryo transfer (ET) and throughout the luteal phase until ET + 14 from patients consecutively enrolling for IVF/ICSI therapy. The luteal phase was supported by vaginal P suppositories only, clinical pregnancies were detected by ultrasound and followed up until the 20th week. Overall pregnancy rate was 30.9% constituting the two study groups of CC (n = 22) and NC cycles (n = 49). Significantly, higher E2 (3326 ± 804 versus 1072 ± 233 pmol/l, p = 0.014) and P (244 ± 68 versus 73 ± 10 nmol/l, p = 0.023) were present in CC versus NC from as early as ET + 7. In the CC group, patients with ongoing pregnancies (CC-OG) as compared with miscarriages (CC-MC) had significantly higher E2 and P from ET + 7, predicting ongoing pregnancy in receiver operator characteristics analysis.
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Affiliation(s)
- Barbara Sonntag
- Department of Gynaecology and Obstetrics, University Hospital Münster, Münster, Germany.
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