HCG

Abstract

Early serum beta-human chorionic gonadotropin (β-hCG) levels are commonly used to assess pregnancy viability following in vitro fertilization (IVF). However, their predictive value for live birth remains uncertain.

Abstract

Testosterone (T) produced by Leydig cells (LCs) is essential for male reproduction; yet, the regulatory mechanisms underlying steroidogenesis remain incompletely understood. Here, we investigated the role of cyclin-dependent kinase 5 regulatory subunit-associated protein 3 (CDK5RAP3) in Leydig cell development and steroidogenesis, based on its identification by immunoprecipitation-mass spectrometry (IP-MS) as a protein associated with steroidogenesis and cholesterol metabolism in mouse testicular tissue. Using human samples, we found that CDK5RAP3 expression was significantly reduced in Leydig cells from patients with spermatogenic failure (T < 10.4 nmol/L). Notably, CDK5RAP3 expression increased during mouse postnatal Leydig cell maturation and regeneration in an ethane dimethanesulfonate (EDS)-induced rat model. Functional analyses in primary LCs and MLTC-1 cells showed that hCG stimulation triggered CDK5RAP3 nuclear translocation without altering its overall expression, while CDK5RAP3 knockdown markedly impaired hCG-induced testosterone production and reduced the expression of the steroidogenic regulator steroidogenic acute regulatory (STAR) protein, as well as key steroidgenic enzymes, including cytochrome P450 family 11 subfamily A member 1 (CYP11A1), 17a-hydroxylase (CYP17A1), and 3β-hydroxysteroid dehydrogenase (HSD3B). Conversely, CDK5RAP3 overexpression enhanced testosterone production in the absence of hCG. In vivo, AAV2/9-mediated CDK5RAP3 silencing in adult mouse testes resulted in a significant reduction in serum testosterone levels compared with controls (3.60 ± 0.38 ng/mL vs. 1.83 ± 0.37 ng/mL). Mechanistically, CDK5RAP3 interacted with SMAD4 and CEBPB, and BMP pathway inhibition by Noggin rescued the testosterone deficit caused by CDK5RAP3 loss. Together, these findings identify CDK5RAP3 as an essential regulator of Leydig cell steroidogenesis and provide insight into its potential relevance to male infertility associated with low testosterone.

Abstract

Serum progesterone (P) levels are critical for endometrial receptivity and implantation in frozen-thawed embryo transfer (FET) cycles. However, the prognostic role of P levels measured on the day of the β-human chorionic gonadotropin (β-hCG) pregnancy test has not been fully elucidated. This study aimed to evaluate the association between β-hCG day serum P levels and pregnancy outcomes in FET cycles. This retrospective cohort study included 621 FET cycles performed between January 2023 and December 2024, of which 79.5% were conducted using hormone replacement therapy (HRT) protocols and 20.5% using natural cycle (NC) protocols. Serum P levels were measured on the day of the β-hCG pregnancy test. Receiver operating characteristic (ROC) curve analysis was used to determine protocol-specific P thresholds for predicting ongoing pregnancy (OPR). Ongoing pregnancy was defined as a viable intrauterine pregnancy confirmed by ultrasound at or beyond 12 weeks of gestation. Multivariable logistic regression was applied to identify independent predictors of OPR. ROC analysis identified optimal P thresholds of 15.5 ng/mL in NC cycles (AUC 0.821) and 14.15 ng/mL in HRT cycles (AUC 0.595). Overall, 44% of patients had serum P levels below the protocol-specific threshold. OPR was significantly higher in patients with P levels above the threshold (NC: 63.0% vs. 12.8%; HRT: 48.1% vs. 31.9%; p < 0.001). Multivariable regression demonstrated that younger maternal age and higher β-hCG day P levels independently predicted OPR. In HRT cycles, blastocyst-stage transfer was also significantly associated with improved outcomes (OR = 0.27, 95% CI 0.13-0.59; p < 0.05). Serum P levels measured on the day of the β-hCG test are significantly associated with pregnancy outcomes in both HRT and NC FET cycles. Routine monitoring of late luteal P levels and individualized luteal phase support strategies may enhance clinical success rates.

Abstract

While in singleton pregnancies the maternal serum biomarkers used in the first-trimester screening for aneuploidies, particularly PAPP-A, may be, also, used as predictors of adverse perinatal outcomes, there is a scarcity of data regarding the association of first-trimester biomarkers with unfavorable pregnancy outcomes in twin pregnancies. The main purpose of our study was to evaluate the association of low PAPP-A levels in twin pregnancies with the subsequent development of perinatal complications.

Abstract

To re-analyse and update a decision tree developed 20 years ago to counsel women regarding the likelihood of successful expectant management of tubal ectopic pregnancies. The original model was developed using the data from 179 cases.

Abstract

Positive human chorionic gonadotropin (hCG) test results have been associated with unnecessary workup and treatment, including invasive procedures and chemotherapy. It is important for health care professionals to consider alternative explanations for positive hCG results when pregnancy and malignancy have been excluded, particularly before proceeding with more invasive interventions. Due to the multiple potential etiologies of persistently elevated hCG, health care professionals should evaluate test results according to a systematic framework. When serum hCG test results are elevated, the first steps are to evaluate for pregnancy (both intrauterine and ectopic). Appropriate retesting to rule out various etiologies and to identify the main cause of persistently elevated hCG is necessary to avoid misdiagnosis or mismanagement of elevated hCG levels.

Abstract

Giant cell tumor of bone (GCTB) is a rare but locally aggressive neoplasm which most commonly arises in the epiphyses of long bones of young adults. Occurrence in the mandible is uncommon, and hormone secreting variants are extremely rare.

Abstract

This study investigates how clinical factors and hormonal levels affect oocyte retrieval in modified natural cycles, aiming to improve understanding and enhance treatment protocols.

Abstract

A limited period of endometrial receptivity is defined by molecular interactions between the embryo and maternal tissues, which are crucial for successful implantation. The results of clinical studies assessing intrauterine human chorionic gonadotropin (hCG) as an endometrial priming agent in in vitro fertilisation (IVF) have been inconsistent, markedly affected by dose, timing, and cycle context. This narrative review summarises molecular data demonstrating that hCG modulates immunological, stromal, endothelial, and epithelial compartments in a coordinated manner, affecting essential endometrial processes. hCG promotes adhesion competence and proliferation in the epithelium via a microRNA-regulated signalling axis (miR-126-3p-PIK3R2-PI3K/Akt). Intrauterine hCG promotes controlled apposition and invasion at the vascular interface by selectively strengthening endothelial junctional cohesion via VE-cadherin and CD146, without promoting angiogenesis. hCG collaborates with ERK/mTOR signalling to regulate autophagy and apoptosis, alters steroid-receptor networks in the stroma, initiates early decidual and survival markers (ACTA2, NOTCH1, complement C3), and enhances stress resistance. hCG modifies the immunological milieu by enhancing the activity of regulatory T cells and altering the distribution of uterine natural killer cells. This facilitates immunological tolerance and the remodelling of spiral arteries. These pleiotropic effects together enhance biomarkers and provide a scientific justification for context-dependent clinical responses, including patient-chosen, directed methods for the delivery of intrauterine hCG during IVF.

Abstract

A hydatidiform mole (HM) is the most common form of gestational trophoblastic disease (GTD). Differentiating hydatidiform moles (HMs) from non-molar pregnancies and distinguishing complete HMs (CHMs) from partial HMs (PHMs) remains challenging due to overlapping morphological features and a high rate of misclassification. This study aimed to evaluate reliable immunohistochemical markers for improving diagnostic accuracy and addressing the limitations of current molecular techniques. We retrospectively analyzed 64 cases of HMs and hydropic abortions (HAs), diagnosed in women aged 17-36 years between 2010 and 2024, at the Pathology Department of "Elena Doamna" Clinical Hospital, Iași, Romania. Routine histology was supplemented with immunohistochemistry (IHC) using p57, Ki-67, β-hCG, and E-cadherin, with semiquantitative immunoscores applied. Histology revealed 38 PHMs (59.37%), 16 CHMs (23.88%), and 10 HAs (15.62%). p57 was positive in 100% of PHMs and HAs but only in 18% of CHMs. Ki-67 expression was predominantly strong in CHMs, variable in PHMs, and weak in all HAs. β-hCG showed the highest expression in CHMs, followed by PHMs and HAs, while E-cadherin was strongest in HAs. Morphological features alone are insufficient for HM diagnosis; thus, ancillary techniques like p57 IHC and DNA genotyping are crucial to differentiate complete, partial moles, and non-molar specimens by revealing unique genetic patterns, especially p57 absence in CHMs and ploidy/parental origin in PHMs. In this context, an algorithmic approach integrating histology, immunohistochemistry, and genotyping reduces interobserver variability and refines diagnostic precision.

Abstract

Ovulation and granulosa cell luteinization are induced by ovulatory signals, including luteinizing hormone (LH) and human chorionic gonadotropin (hCG). Histone modifications enable rapid, signal-responsive transcriptional reprogramming. However, the effects of LH/hCG-induced histone modification changes on the mural granulosa cells (MGCs) function remain to be fully elucidated. By mining public datasets we integrated transcriptomic and histone-modification profiles of MGCs across the ovulatory interval and tracked LH/hCG-driven gene expression at three time points (0, 4, and 12 h after-hCG). During oocyte maturation, the 4 h LH-surge constitutes a critical window for meiotic resumption, during which many genes display rapid transcriptional changes followed by a return to baseline levels. Early-response genes are enriched for cell locomotion, inflammatory responses, the activation of signaling pathways, and histone modifications. Furthermore, LH/hCG-induced transcriptome remodeling is highly correlated with dynamic gains or losses of H3K4me3 and H3K27ac. Notably, we discovered for the first time that H3K27ac marks super-enhancers (SEs) that regulate LH/hCG-induced transcriptional activation in MGCs. Finally, through complementary in vitro and in vivo pharmacological inhibition, we demonstrate that LH/hCG governs oocyte maturation and ovulation by reshaping the MGC transcriptome via H3K4me3- and H3K27ac-dependent chromatin remodeling. In summary, our study advances the understanding of how gonadotropins regulate MGC function and oocyte maturation through histone-modification-mediated transcriptional control.

Abstract

This study analyzed clinical pregnancy outcomes in patients undergoing in vitro fertilization-embryo transfer with donor sperm (IVF-D) using different ovulation induction protocols, to provide reference data for selecting appropriate protocols.

Abstract

Gestational trophoblastic neoplasia (GTN) rarely presents concurrently in mother and infant, with very few cases reported worldwide. We describe an infant who presented with vomiting, lethargy and hepatomegaly. Emergency ultrasound revealed hepatomegaly, and contrast-enhanced CT showed large bilobar hepatic lesions with central necrosis and multiple bilateral pulmonary nodules. Despite supportive care, the infant's condition deteriorated, resulting in death. Post-mortem liver biopsy confirmed metastatic GTN. Shortly thereafter, the mother developed neurological symptoms; brain MRI revealed a haemorrhagic lesion, and chest CT demonstrated pulmonary metastases. Elevated serum beta-human chorionic gonadotropin (β-hCG) confirmed metastatic choriocarcinoma. MRI was not performed in the infant due to the rapid clinical decline and the need for prolonged sedation, which posed significant risk. This case highlights the importance of considering GTN in infants with atypical hepatic and pulmonary lesions, especially when there is a recent maternal pregnancy. Early β-hCG testing and timely imaging can facilitate diagnosis and improve outcomes for both mother and child.

Abstract

Domestic pigs have become increasingly important models in translational research; however, their large size presents logistical and ethical challenges. Microminipigs offer a practical alternative for long-term studies. This study aimed to develop an effective superovulation protocol using a step-down follicle-stimulating hormone (FSH) regimen to improve zygote collection in microminipigs.

Abstract

This study aimed to analyze the effect of progesterone (P) levels on the human chorionic gonadotropin (hCG) trigger day and the progesterone on hCG day-to-basal progesterone (PhCG/Pbasal) ratio on pregnancy outcomes in patients with a normal ovarian response undergoing fresh embryo transfer in a gonadotropin-releasing hormone antagonist (GnRH-ant) cycle.

Abstract

The aim was to evaluate the effects of administering long-acting injectable progesterone (iP4) and/or hCG 3 days after timed artificial insemination (TAI) on luteal dynamics, circulating progesterone (P4) concentrations, and fertility outcomes of lactating dairy cows. In experiment 1, synchronized lactating Holstein cows (n = 29) were treated 24 h after induction of luteolysis with 0, 300, 600, or 900 mg of iP4 i.m. to determine circulating P4 profiles over 9 d. In experiment 2, synchronized lactating Holstein cows (n = 75) were allocated in a 2 × 2 factorial design to receive no treatment (Control), 900 mg of iP4 (iP4), 2000 IU hCG (hCG), or both (iP4+hCG) on day 3 of the estrous cycle (day 0 = expected day of endogenous GnRH surge). Ovarian ultrasonography and blood sampling were performed to evaluate corpus luteum (CL) volume and circulating P4 concentrations. In experiment 3, lactating Holstein cows (n = 980) from two farms were synchronized, submitted to TAI on Day 0, and assigned on Day 3 to the same treatments described in experiment 2. Pregnancy diagnosis was performed by ultrasonography on Days 30 and 60 to assess pregnancy per AI (P/AI) and pregnancy loss (PL). In experiment 1, iP4 increased circulating P4 in a dose-dependent manner, with the 900 mg dose producing the highest (P < 0.01) mean P4 concentrations (1.8 ± 0.2 ng/mL) over 9 d. In experiment 2, no iP4 × hCG interaction was observed. The iP4 treatment increased (P < 0.01) circulating P4 on Days 5 and 7 without affecting CL development (P = 0.45), while hCG increased CL volume on Days 9 and 13 (P < 0.01), and P4 concentrations on Day 9 (P = 0.05). In experiment 3, there was no effect of hCG nor interaction iP4 × hCG on fertility outcomes. However, iP4 increased overall P/AI at 30 days (34.3 [170/495] vs. 26.6% [129/485]; P < 0.01), with effects depending on farm and season. The beneficial effect of iP4 on fertility outcomes was observed only on one of the farms, and only during the hot season. In conclusion, hCG treatment 3 days after TAI transiently increased CL volume and P4 concentrations but did not improve fertility. Conversely, iP4 supplementation increased circulating P4 without impairing CL function and improved fertility of lactating dairy cows, although this benefit appeared conditional on environmental and management factors.

Abstract

Background and Objectives: To evaluate the impact of gonadotropin-releasing hormone agonist (GnRHa) triggering compared to human chorionic gonadotropin (hCG) triggering on frozen-thawed and fresh embryo transfer outcomes in patients with polycystic ovary syndrome (PCOS) undergoing in vitro fertilization (IVF). Materials and Methods: This retrospective cohort study analyzed 267 IVF cycles of 261 PCOS patients treated with GnRH antagonist protocols. Patients were divided into three groups: GnRHa-triggered frozen-thawed embryo transfer (ET) (n = 126), hCG-triggered frozen-thawed ET (n = 68), and hCG-triggered fresh ET (n = 73). Baseline characteristics, stimulation parameters, and cycle outcomes were compared between groups. A binary logistic regression analysis was established to identify independent predictors of clinical pregnancy. Results: The GnRHa-triggered group had significantly higher numbers of retrieved oocytes, mature (MII) oocytes, and fertilized oocytes compared to both hCG-triggered groups (p < 0.001). The number of obtained embryos and frozen embryos (good-quality embryos) was highest in the GnRHa group (p < 0.001). However, clinical pregnancy rates were comparable between the groups with a similar number and grade of transferred embryos (32.53%, 38.23%, and 32.87%, respectively). Multivariate regression analysis revealed that the grade of the transferred embryo was a significant predictor of clinical pregnancy (p = 0.034). Conclusions: This study provides insights into different triggering strategies for final oocyte maturation in PCOS patients. GnRH-agonist-triggered frozen-thawed cycles showed comparable clinical pregnancy outcomes to those of hCG-triggered cycles, with a potentially lower OHSS risk. The findings suggest that individualized triggering approaches based on patient characteristics and OHSS risk may be beneficial for PCOS patients undergoing IVF.

Abstract

High-altitude acclimatization triggers physiological adaptations - such as increased ventilation, heart rate, and red blood cell production - to improve tissue oxygen delivery. These adaptations may obscure typical signs of hemorrhage, complicating the diagnosis of ruptured ectopic pregnancy in patients with low beta-human chorionic gonadotropin (β-hCG) levels.

Abstract

The final trigger of oocyte maturation is a pivotal step in assisted reproductive technology (ART). Different molecules and protocols-including human chorionic gonadotropin (hCG), gonadotropin-releasing hormone agonists (GnRHa), the dual trigger, the double trigger, and emerging agents such as kisspeptin-have been investigated to optimize oocyte competence, embryo development, and pregnancy outcomes while minimizing the risk of ovarian hyperstimulation syndrome (OHSS). HCG remains the most widely used trigger, but its pharmacological profile is associated with a significant risk of OHSS. GnRHa has emerged as an alternative in antagonist cycles, abolishing the risk of severe OHSS but often requiring tailored luteal phase support. Several strategies, including hCG, GnRHa, and combined approaches, have shown improvements in specific outcomes such as the oocyte maturity (MII) rate, fertilization rate, embryo development parameters, and, in selected contexts, a reduction in OHSS risk. Kisspeptin represents a promising option; however, its use remains predominantly within the research setting, with clinical application still limited to early-phase or highly selected studies. Beyond the choice of molecule, the timing of trigger administration-adjusted to follicle size, estradiol concentrations, and progesterone levels-also influences oocyte competence and subsequent clinical outcomes. Triggering final oocyte maturation remains a multifaceted decision that should be individualized according to patient characteristics, ovarian response, and risk of OHSS. Although hCG remains the historical reference standard, accumulating but heterogeneous evidence suggests that GnRHa-based strategies, including dual-trigger protocols, may improve specific outcomes in selected patient subgroups. However, results across trials are inconsistent, particularly in poor responders, and any exposure to hCG maintains a residual risk of OHSS. Kisspeptin represents a promising but still experimental option, with current data largely limited to early-phase clinical studies in highly selected high-risk populations. Well-designed randomized trials are required to clarify the true impact of these strategies on live birth, to refine timing and dosing, and to better define which patients are most likely to benefit.

Abstract

Molar pregnancy is an uncommon diagnosis in perimenopausal women and poses a high risk of complications, including hemorrhagic shock and malignant transformation. We report the case of a 51-year-old woman who presented with severe abdominal pain and profuse vaginal bleeding. Imaging revealed a markedly enlarged uterus with a large intracavitary mass, and serum β-hCG levels were elevated. The patient developed hemorrhagic shock and underwent an emergency hemostatic hysterectomy. Histopathological examination confirmed a complete hydatidiform mole with early invasive features, without choriocarcinoma. Postoperative imaging showed no metastases, and the patient received methotrexate-based chemotherapy with favorable response, evidenced by a progressive decline in β-hCG levels. This case underscores the importance of considering gestational trophoblastic disease in the differential diagnosis of abnormal uterine bleeding in perimenopausal women. Early recognition and timely surgical intervention, followed by appropriate chemotherapy and monitoring, are crucial to avoid potentially life-threatening complications.

Abstract

The study of ovarian biology is hampered by the lack of in vitro models that faithfully recapitulate the physiology of granulosa cells (GCs). Primary GCs have a limited lifespan, while most immortalized lines are tumor-derived and exhibit non-physiological hormonal responses. The purpose of this study was to develop and characterize a novel immortalized GC line with a stable, physiologically relevant phenotype. We immortalized primary murine GCs from early antral follicles using lentiviral vector to introduce human telomerase reverse transcriptase (hTERT) gene to create the IMG-A1 cell line. The line was extensively characterized using molecular (qRT-PCR, Western blot), cytogenetic (karyotyping), and functional (hormone stimulation, ELISA, proliferation assays) methods to assess its phenotype and responsiveness to gonadotropins and metabolic stressors. Exhibiting a non-transformed phenotype, IMG-A1 cells retain a stable karyotype and express the follicle-stimulating hormone receptor (FSHR) but not the luteinizing hormone/chorionic gonadotropin receptor (LHCGR). Accordingly, they respond to FSH by upregulating steroidogenic genes like aromatase (Cyp19a1) but are unresponsive to LH/hCG. Furthermore, the line exhibits physiologically relevant responses to hormonal stimulation, including a strong induction of aromatase by FSH and its synergistic upregulation in a hyperandrogenic and hyperinsulinemic milieu. The IMG-A1 cell line is a unique and robust model of early antral granulosa cells, offering a valuable new tool for studying FSH-dependent folliculogenesis, cellular aspects of ovarian pathophysiology, and drug discovery.

Abstract

Oral submucous fibrosis (OSF) has a high propensity for malignant transformation, and oral squamous cell carcinoma (OSCC) associated with OSF exhibits different clinical and pathological features compared to non-OSF-related OSCC. It aimed to investigate the expression characteristics of peripheral blood interleukins (ILs) in patients with OSF-related OSCC and their relationship with clinical and pathological features.

Abstract

The objective of this study was to assess the trade-off between cycle continuation and cancellation in slow ovarian response (SOR) patients, and to evaluate the impact of SOR on embryo developmental potential and clinical pregnancy outcomes.

Abstract

Non-gestational choriocarcinomas (NGCCs) are extremely rare and aggressive tumours that can develop without pregnancy. We present three cases in postmenopausal women in their early 60s and 70s who presented with abdominal symptoms. Evaluation included imaging, histopathology, immunohistochemistry and elevated serum β-hCG. One patient showed a partial response to chemotherapy, while two had disease progression and died. The case series illustrates the need for consideration of NGCC in older women with elevated β-hCG and no recent pregnancy, and the crucial role of early immunohistochemical diagnosis.

Abstract

Cervical pregnancy is a rare form of ectopic pregnancy that occurs in the cervical canal. Diagnosis and treatment are particularly challenging when the lesion is large and presents without typical symptoms. Here we report a case of cervical pregnancy with placenta accrete.

Abstract

Poor ovarian response (POR) remains a major limitation in assisted reproductive medicine. Direct comparisons between r-hFSH alfa + r-LH and r-hFSH delta + hMG in this population are scarce.

Abstract

Dual triggering is recommended in most cases with GnRH antagonists for final oocyte maturation. Although no definitive data support the routine use of dual triggering in normal responders, recent meta-analyses have indicated benefits linked to dual triggering regarding improved reproductive outcomes (oocyte maturation, embryo quality, and clinical pregnancy). Therefore, dual triggering may be considered the preferred trigger for all patients undergoing IVF with antagonist blockade cycles (ORPI in ranges A and B (without hCG dose reduction) and in cases of ORPI in ranges C and D (with hCG dose reduction). Finally, rigorous clinical assessment is essential when an isolated GnRHa trigger is combined with low-dose hCG to correct an inadequate luteal phase. In these cases, the freezing all protocol cannot be ignored.

Abstract

Previous studies have shown that elevated progesterone (P4) levels on human chorionic gonadotropin (HCG) trigger days may affect endometrial tolerance. However, no standardized threshold has been established for the impact of late follicular phase P4 on clinical outcomes. This study aimed to assess the influence of P4 levels on the day of HCG trigger in a follicular long-term protocol on clinical outcome.

Abstract

Ovarian hyperstimulation syndrome (OHSS) is a serious complication commonly encountered in patients with infertility undergoing ovulation induction therapy. This study investigates histomorphological and biochemical effects of melatonin in an experimental OHSS model. Rats were divided into four groups: control group, controlled ovarian stimulation group (COS), ovarian hyperstimulation syndrome group (OHSS), and ovarian hyperstimulation syndrome + melatonin group (OHSS + melatonin). OHSS was induced in the OHSS and OHSS + melatonin groups by pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG) injections, followed by melatonin treatment administered intraperitoneally at a dose of 50 mg/kg only in the OHSS + melatonin group. In the OHSS group, ovarian weight increased and the number of atretic follicles also rose, while melatonin treatment improved these conditions. Histological analysis showed that melatonin preserved ovarian structure and supported follicular development. Serum estradiol levels were significantly higher in the OHSS group compared with the control group, but melatonin treatment reduced these levels significantly. Peritoneal fluid levels of vascular endothelial growth factor (VEGF) and interleukin (IL)-6 were elevated in the OHSS group, but melatonin treatment decreased these levels. Additionally, melatonin reduced follicular atresia and increased the number of Graafian follicles. In conclusion, melatonin improved the biochemical and histological markers of OHSS, providing protective effects on ovarian function. These findings suggest that melatonin could be a potential therapeutic agent for the treatment of OHSS. However, further clinical and experimental studies are needed to investigate its effects.

Abstract

Vaspin, a visceral-adipose-tissue-derived serine protease inhibitor, is involved in the development of obesity, insulin resistance, energy metabolism, and reproduction. Its expression and regulation were studied in the human and rat placenta; however, the role of this adipokine in placental endocrine function has never been studied. The present study aimed to investigate the in vitro effects of vaspin on the endocrine function of the human placental syncytiotrophoblasts BeWo cell line and villous explants collected during the third trimester of pregnancy. BeWo cells (n=4) or villous explants (n=3) were cultured with vaspin at doses of 0.1, 1, and 10 ng/ml for 24, 48, and 72 h. The levels of progesterone (P4), estradiol (E2), human chorionic gonadotropin (hCG), and human placental lactogen (hPL) were determined in the culture medium via enzyme-linked immunosorbent assay (ELISA). In addition, the mRNA and protein expression of 3β-hydroxysteroid dehydrogenase (HSD3B1/3βHSD), aromatase (CYP19A1/CYP19), CGB3/hCG, and CSH1/hPL were determined via real-time PCR and Western blotting, respectively. We analyzed the role of pharmacological inhibitors of extracellular signal-regulated kinase (ERK1/2) and protein kinase A (PKA) in the vaspin action on hormone secretion. We observed that vaspin has a modulatory effect on the secretion and expression of placental hormones in BeWo cells and placentas from physiological pregnancies. However, in most cases, the effect was inhibitory on the parameters examined. Moreover, we noted that PKA participates in reducing E2 secretion, while ERK1/2 is involved in hCG level. These findings indicate that vaspin is a new regulator of human placental endocrine function.