Factors affecting biochemical pregnancy loss (BPL) in preimplantation genetic testing for aneuploidy (PGT-A) cycles: machine learning-assisted identification.

PURPOSE: To determine the factors influencing the likelihood of biochemical pregnancy loss (BPL) after transfer of a euploid embryo from preimplantation genetic testing for aneuploidy (PGT-A) cycles. METHODS: The study employed an observational, retrospective cohort design, encompassing 6020 embryos from 2879 PGT-A cycles conducted between February 2013 and September 2021. Trophectoderm biopsies in day 5 (D5) or day 6 (D6) blastocysts were analyzed by next generation sequencing (NGS). Only single embryo transfers (SET) were considered, totaling 1161 transfers. Of these, 49.9% resulted in positive pregnancy tests, with 18.3% experiencing BPL. To establish a predictive model for BPL, both classical statistical methods and five different supervised classification machine learning algorithms were used. A total of forty-seven factors were incorporated as predictor variables in the machine learning models. RESULTS: Throughout the optimization process for each model, various performance metrics were computed. Random Forest model emerged as the best model, boasting the highest area under the ROC curve (AUC) value of 0.913, alongside an accuracy of 0.830, positive predictive value of 0.857, and negative predictive value of 0.807. For the selected model, SHAP (SHapley Additive exPlanations) values were determined for each of the variables to establish which had the best predictive ability. Notably, variables pertaining to embryo biopsy demonstrated the greatest predictive capacity, followed by factors associated with ovarian stimulation (COS), maternal age, and paternal age. CONCLUSIONS: The Random Forest model had a higher predictive power for identifying BPL occurrences in PGT-A cycles. Specifically, variables associated with the embryo biopsy procedure (biopsy day, number of biopsied embryos, and number of biopsied cells) and ovarian stimulation (number of oocytes retrieved and duration of stimulation), exhibited the strongest predictive power.

Direct embryonic biopsy with transcervical embryoscopy is an effective method for karyotyping and morphology assessment in miscarriages.

PURPOSE: The main purpose of this study is to compare the validity of transcervical embryoscopy method with standard uterine evacuation method in detecting more accurate karyotypes in miscarriages below tenth week of pregnancy. Additionally, the frequency and distribution of fetal morphological abnormality were evaluated. METHODS: A prospective study was carried out at the Gazi University Faculty of Medicine, Department of Obstetrics and Gynecology. Patients with missed abortions between sixth and tenth gestational weeks were included in the study group, and fetal morphological examination and direct embryonic biopsy were performed by transcervical embryoscopy. The control group consisted of patients who experienced miscarriage and genetic material obtained from routine uterine evacuation between February and October 2023. RESULT: A total of 60 patients in the study group and 189 patients in the control group were evaluated. The median ages, previous miscarriage numbers, median gravida numbers, and median gestational weeks were comparable between groups. Chromosomal abnormality was detected in 24 (42.8%) and 52 embryos (29.9%) in the study and control groups, respectively (p = 0.004). Culture failure rates were 6.6% (n = 4) and 7.9% (n = 15) in the study and control groups, respectively. In the study group, 12 embryos had a morphological abnormality in which 6 of them had normal karyotype. CONCLUSION: Direct embryonic biopsy with transcervical embryoscopy is an effective method to exclude maternal decidual cell contamination and placental mosaicism in miscarriages for karyotype analysis. In addition, detecting anomalies in morphology might contribute our understanding in the process of miscarriages which arises independent from structural/numerical chromosomal abnormalities.

Diagnostic utility of clinicodemographic, biochemical and metabolite variables to identify viable pregnancies in a symptomatic cohort during early gestation.

A significant number of pregnancies are lost in the first trimester and 1-2% are ectopic pregnancies (EPs). Early pregnancy loss in general can cause significant morbidity with bleeding or infection, while EPs are the leading cause of maternal mortality in the first trimester. Symptoms of pregnancy loss and EP are very similar (including pain and bleeding); however, these symptoms are also common in live normally sited pregnancies (LNSP). To date, no biomarkers have been identified to differentiate LNSP from pregnancies that will not progress beyond early gestation (non-viable or EPs), defined together as combined adverse outcomes (CAO). In this study, we present a novel machine learning pipeline to create prediction models that identify a composite biomarker to differentiate LNSP from CAO in symptomatic women. This prospective cohort study included 370 participants. A single blood sample was prospectively collected from participants on first emergency presentation prior to final clinical diagnosis of pregnancy outcome: LNSP, miscarriage, pregnancy of unknown location (PUL) or tubal EP (tEP). Miscarriage, PUL and tEP were grouped together into a CAO group. Human chorionic gonadotrophin ß (ß-hCG) and progesterone concentrations were measured in plasma. Serum samples were subjected to untargeted metabolomic profiling. The cohort was randomly split into train and validation data sets, with the train data set subjected to variable selection. Nine metabolite signals were identified as key discriminators of LNSP versus CAO. Random forest models were constructed using stable metabolite signals alone, or in combination with plasma hormone concentrations and demographic data. When comparing LNSP with CAO, a model with stable metabolite signals only demonstrated a modest predictive accuracy (0.68), which was comparable to a model of ß-hCG and progesterone (0.71). The best model for LNSP prediction comprised stable metabolite signals and hormone concentrations (accuracy = 0.79). In conclusion, serum metabolite levels and biochemical markers from a single blood sample possess modest predictive utility in differentiating LNSP from CAO pregnancies upon first presentation, which is improved by variable selection and combination using machine learning. A diagnostic test to confirm LNSP and thus exclude pregnancies affecting maternal morbidity and potentially life-threatening outcomes would be invaluable in emergency situations.

Copy number variation sequencing for the products of conception: What is the optimal testing strategy.

BACKGROUND: Copy number variation sequencing (CNV-seq) is crucial in prenatal diagnosis, but its limitations in detecting polyploidy, maternal cell contamination (MCC), and uniparental disomy (UPD) restrict its application in the analysis of products of conception (POCs). This study aimed to investigate an optimal genetic testing strategy for POCs in the era of CNV-seq. METHODS: CNV-seq and quantitative fluorescent polymerase chain reaction (QF-PCR) were performed in all 4,211 spontaneous miscarriage cases. Different testing strategies were compared and the optimal testing strategies were proposed. RESULTS: Of the 4,211 cases, 2561 (60.82%) exhibited clinically significant chromosomal abnormalities. CNV-seq alone, without QF-PCR, might misdiagnose 311 (7.39%) cases, including 278 polyploidy, 13 UPD, and 20 MCC. In 20 MCC cases identified by QF-PCR, CNV-seq successfully pinpointed the cause of miscarriage in 13 cases. Furthermore, in cases where QF-PCR suggested polyploidy, CNV-seq improved the diagnostic accuracy in 54 (1.28%) hypo/hypertriploidy cases. After comparing four different strategies, the sequential approach (initiating with CNV-seq followed by QF-PCR if necessary) emerged as advantageous, reducing approximately 70% of the cost associated with QF-PCR while maintaining result accuracy. CONCLUSIONS: We propose an initial CNV-seq followed by QF-PCR if needed-an efficient and cost-effective strategy for the genetic analysis of POCs.

Diagnostic value of neutrophil-to-lymphocyte and platelet-to-lymphocyte ratio to predict recurrent pregnancy loss and abortion; a systematic review and meta-analysis.

OBJECTIVE: This systematic review and meta-analysis aimed to evaluate the diagnostic value of the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in women with a history of abortion (missed and threatened) and recurrent pregnancy loss (RPL) in comparison with healthy pregnancies. METHODS: Electronic databases including MEDLINE, Scopus, Web of Science, Embase, and Cochrane Library were searched for NLR and PLR in women who experienced early pregnancy loss up to January 1, 2023 with a combination of proper keywords. Meta-analysis was done for comparison with three or more studies and summary estimates were measured. RESULTS: A total of 390 citations were retrieved initially, and after screening, 16 articles were deemed eligible for the final review. Among these, 14 studies underwent meta-analysis. The meta-analysis revealed that the standard mean of the NLR was significantly higher in abortion cases compared to the control group. However, there was no significant difference in the PLR between the pregnancy loss group and the control group. CONCLUSION: NLR was significantly higher among RPL patients compared to the control group, according to these data, NLR may be capable of being used in the diagnosis of RPL as an easy, cheap, and accessible modality. Further studies, which take these variables into account, will need to be undertaken to determine the diagnostic value of NLR and PLR in early pregnancy loss.

Expression and clinical significance of miR-141-5p as a biomarker in the serum of patients with early spontaneous abortion.

AIM: miR-141-5p expression in patients with Early Spontaneous Abortion (ESA) and its correlation with hormone levels during pregnancy were investigated. METHODS: A total of 70 pregnant women with ESA were selected as the research group, and 70 normal pregnant women who chose abortion for non-medical reasons were selected as the Con group. Serum ß-HCG, Progesterone (P), and Estrogen (E2) were detected by enzyme-linked immunosorbent assay. Differentially expressed miRNAs were screened by miRNA microarray analysis. miR-141-5p expression was detected by RT-qPCR, and its correlation with serum ß-HCG, P, and E2 levels was analyzed. The diagnostic value of miR-141-5p for ESA was evaluated by the ROC curve. RESULTS: Serum ß-HCG, P, and E2 were decreased and serum miR-141-5p was increased in patients with ESA. Pearson correlation analysis showed that serum ß-HCG, P, and E2 levels were negatively correlated with miR-141-5p expression levels. ROC curve showed that miR-141-5p had a diagnostic value for ESA. CONCLUSIONS: miR-141-5p is related to hormone levels during pregnancy and is expected to become a new candidate diagnostic marker for ESA.

Evaluation of Combined p57KIP2 Immunohistochemistry and Fluorescent in situ Hybridization Analysis for Hydatidiform Moles Compared with Genotyping Diagnosis.

Immunostaining with p57KIP2 is a widely used diagnostic technique to differentiate complete hydatidiform moles (CHMs) from partial hydatidiform moles (PHM) and non-molar hydropic abortion. However, distinguishing between PHMs and non-molar hydropic abortions using histopathology alone is often challenging. This study aimed to evaluate the technical validity and additional benefits of using fluorescence in situ hybridization (FISH) in combination with p57KIP2 immunostaining to diagnose molar and non-molar conceptuses. The study involved 80 specimens, which underwent genetic diagnosis using short tandem repeat analysis, including 44 androgenetic CHMs, 20 diandric monogynic PHMs, 14 biparental non-molar hydropic abortions, 1 monoandric digynic triploid abortion, and 1 vaginal specimen of gestational trophoblastic neoplasia. Two pathologists independently diagnosed the cases based on morphology and p57KIP2 immunostaining while the clinical information was masked. FISH analysis was performed using 3 probes (CEP17, CEPX, and CEPY), which revealed that all androgenetic CHM and biparental diploid non-molar hydropic abortion specimens were diploid. Among the 20 diandric monogynic PHM cases examined by analyzing short tandem repeat polymorphisms, 18 were triploid, and the remaining 2 were diploid. These two specimens were possibly androgenetic/biparental mosaics based on FISH analysis, where the three-signal ratios counting 50 cells were clearly within the diploid ranges. Eight of the 20 genetic PHMs and 2 of the 14 genetically confirmed non-molar hydropic abortions that were falsely diagnosed based on morphology and immunohistochemistry by at least 1 pathologist were correctly diagnosed as PHM and non-molar hydropic abortion, respectively, by FISH analysis. However, 1 monoandric digynic villus was classified as triploid by FISH analysis, leading to a false PHM diagnosis. In conclusion, the combination of FISH analysis with p57KIP2 immunostaining helps in diagnosing molar and non-molar conceptuses in numerous cases; nevertheless, exceptional cases should be considered.

A prospective study to evaluate whether serum kisspeptin is a marker predictive of the first-trimester miscarriage of women who conceive in IVF.

PURPOSE: Kisspeptin is an emerging biomarker for the discrimination of viable pregnancy. The aim of the study is to determine whether serum kisspeptin can predict the first-trimester miscarriage and compare it with serum HCG in the prediction of the first-trimester miscarriage. METHODS: This study is a prospective case-control design including 178 women who had experienced early miscarriage (n = 21) and viable single pregnancy (n = 157), following frozen-thawed embryo transfer (FET) from May to December 2019. Serum samples on 14 days, 21 days, and 28 days after FET were collected for kisspeptin and HCG detection. TRIAL REGISTRATION NUMBER: NCT03940495. RESULTS: On day 21 after FET, serum kisspeptin levels were significantly lower in the early miscarriage group [0.260 (0.185-0.375)] vs in the viable single-pregnancy group [0.370 (0.280-0.495)] (p = 0.005). Similar results were shown on day 28 after FET, the serum kisspeptin levels were significantly lower in the early miscarriage group [0.270 (0.200-0.330)] vs in the viable single pregnancy group [0.670 (0.455-1.235)] (p < 0.001). But on day 14 after FET, serum kisspeptin levels were comparable in the early miscarriage group [0.260 (0.210-0.325)] and in the viable single-pregnancy group [0.280 (0.215-0.340)] (p = 0.551). Serum kisspeptin levels on days 21 and 28 have a poor predictive value of miscarriage compared with serum HCG levels. [Day 21: AUC = 0.687 (kisspeptin) and 0.816 (HCG); Day 28: AUC = 0.896 (kisspeptin) and 0.909 (HCG)]. CONCLUSIONS: Serum kisspeptin on day 14 failed to discriminate between miscarriage and ongoing pregnancies, and days 21 and 28 had poor predictive values of miscarriage.

Frozen embryo transfer outcomes decline with increasing female body mass index in female but not male factor infertility: analysis of 56,564 euploid blastocyst transfers.

OBJECTIVE: To evaluate the association of body mass index (BMI) with cycle outcomes after euploid frozen blastocyst transfer. DESIGN: Retrospective cohort study. SETTING: Not applicable. PATIENT(S): A total of 56,564 first single autologous euploid frozen embryo transfers from the 2016-2019 Society for Assisted Reproductive Technology database were analyzed using BMI and using World Health Organization BMI cohorts. Subanalyses were performed on cycles among patients with a sole diagnosis of polycystic ovary syndrome (PCOS) (n = 4,626) and among patients with only a male factor (n = 10,854). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Clinical pregnancy, pregnancy loss, and live birth (LB). RESULT(S): Success rates and adjusted odds ratios (aORs) with 95% confidence intervals (CIs) for all outcomes were most favorable among those with normal BMI and progressively worsened with increasing BMI. These trends persisted among patients with PCOS for clinical pregnancy (aOR, 0.99; 95% CI, 0.98-0.997), pregnancy loss (aOR, 1.02; 95% CI, 1.01-1.04), and LB (aOR, 0.98; 95% CI, 0.97-0.99), but not among patients with a male factor only for clinical pregnancy (aOR, 1.00; 95% CI, 0.99-1.01), pregnancy loss (aOR, 1.01; 95% CI, 0.99-1.03), or LB (aOR, 0.99; 95% CI, 0.98-1.00). CONCLUSION(S): In the largest cohort to date, increasing BMI was associated with decreased pregnancy and LB and increased pregnancy loss after euploid frozen embryo transfers among the entire cohort and among patients with a sole diagnosis of PCOS; however, these results were attenuated among patients with a sole diagnosis of male factor infertility, suggesting that associated female infertility diagnoses and not BMI alone may underlie this trend.

Non-invasive cell-free DNA-based approach for the diagnosis of clinical miscarriage: A retrospective study.

OBJECTIVE: To evaluate cell-free DNA (cfDNA) testing as a non-invasive approach to detecting aneuploidies in clinical miscarriages. DESIGN: A retrospective cohort study of women with pregnancy loss. SETTING: Hospitals and genetic analysis laboratories. POPULATION OR SAMPLE: Pregnancy losses in the period 2021-2022. METHODS: Results derived from non-invasive cfDNA testing (Veriseq NIPT Solution V2) of maternal blood and invasive analysis of products of conception (POC) (Ion ReproSeq) compared in 120 women who suffered a miscarriage. MAIN OUTCOME MEASURES: Concordance rate results, cfDNA testing performance, non-informative rate (NIR) and fetal fraction (FF). RESULTS: We found no significant differences in the NIR between invasive (iPOC) and non-invasive (niPOC) analysis of POC (10.0% [12/120] versus 16.7% [20/120]). Of 120 samples, 90 provided an informative result in iPOC and niPOC groups (75%). cfDNA analysis correctly identified 74/87 (85.1%) samples (excluding triploidies). Sensitivity and specificity were 79.4% and 100%, respectively; all discordant cases were female. A binomial logistic model suggested fetal sex as the only variable influencing the concordance rate (P = 0.035). A Y-chromosome-based FF estimate allowed the optimal reclassification of cfDNA of non-informative male fetuses and a more accurate evaluation of cfDNA testing performance. The difference between the two FF estimates (native algorithm and Y-chromosome-based) suggests that female non-concordant cases may represent non-informative cases. CONCLUSIONS: Cell-free DNA-based testing provides a non-invasive approach to determining the genetic cause of clinical miscarriage.

Double Trisomy 16 and 22 Clinically Mimic Partial Hydatidiform Mole in a Case of Subsequent Pregnancy Loss.

A case of double trisomy 16 and 22 in the second pregnancy loss is presented. DNA analyses (short tandem repeats genotyping) of miscarriage specimen was indicated because of ultrasound suspicion of partial hydatidiform mole. After the partial hydatidiform mole exclusion, further DNA analyses focused on the most common aneuploidies causing pregnancy loss, detected double trisomy 16 and 22 in the product of conception. The couple was referred to clinical genetic consultation and normal parental karyotypes were proved. For further explanatory purposes, archived material from the first pregnancy loss was analyzed and trisomy of chromosome 18 was detected. By comparison of allelic profiles of the mother, father, and both losses, the maternal origin of all aneuploidies was proven what can be attributed to frequent meiosis errors, probably due to advanced maternal age (44 years at the first loss and 45 years at the second loss). In conclusion, aneuploidies can mimic partial hydatidiform mole. Genetic analysis is helpful on the one hand to rule out partial hydatidiform mole and on the other hand to identify aneuploidies and in this way to determine the cause of miscarriage.

Euploid programmed frozen embryo transfer cycles are associated with a higher live birth rate when estradiol levels more closely mimic physiology.

OBJECTIVE: To determine whether peak estradiol (E2) levels above the usual physiologic range (300-500 pg/mL) will impact programmed frozen embryo transfer (FET) outcomes in an ideal study population of those using good-quality single euploid blastocysts. DESIGN: Retrospective cohort study. SETTING: University-based clinic. PATIENTS: Single euploid-programmed FET done at a single academic institution from January 2016 to December 2019. The population was divided into three groups on the basis of peak serum E2 levels during endometrial preparation: group A (E2 <300 pg/mL), group B (300-500 pg/mL), and group C (>500 pg/mL). Group B was used as the reference range for statistical analysis. INTERVENTION: Frozen embryo transfer cycles. MAIN OUTCOME MEASURES: The primary outcome was the live birth rate (LBR). Secondary outcomes included implantation, biochemical, ectopic, and miscarriage rates. RESULTS: A total of 750 FET cycles were included in this study. Poisson regression analysis showed a negative impact of higher peak E2 on the LBR. A decrease in LBR was noted between group C and referent group B (50.2% vs. 63.4%, risk ratio 0.79 [0.68-0.91]) and group A and referent group B (42.5% vs. 63.4%, risk ratio 0.67 [0.46-0.98]). Secondary outcomes were notable for a lower implantation rate when groups A and C were compared with group B and a higher biochemical rate between group C and group B. There was no notable difference between groups in ectopic or miscarriage rates. CONCLUSION: Limiting peak serum E2 levels to 300-500 pg/mL during programmed FET cycles is associated with improved LBRs compared with cycles with peak E2 levels of <300 pg/mL or >500 pg/mL in an ideal study population.

Molecular diagnosis of complete and partial hydatidiform moles.

Complete and partial hydatidiform moles are abnormal products of conception that can be identified by clinical, ultrasonographic, morphologic, histologic, and genetic methods. The diagnosis is usually confirmed only by histological examination. However, accurate diagnosis based on morphological criteria is difficult and some studies have shown that misclassifications are common, even when analysed by highly experienced pathologists. Misdiagnosis may mean that women are either not included in adequate ß-hCG follow-up with the risk that the hydatidiform mole progresses to choriocarcinoma or, conversely, are included in follow-up unnecessarily. A reliable complementary method to pathological interpretation may be genetic analysis of the conceptus to eliminate the diagnostic dilemma by distinguishing non-molar spontaneous abortions from hydatidiform moles and defining the type of hydatidiform mole. The aim of our short paper is to introduce the routine molecular analysis used in our laboratory to a wider range of clinical pathologists.

A simple scoring system for the prediction of early pregnancy loss developed by following 13,977 infertile patients after in vitro fertilization.

A retrospective study was conducted to investigate a convenient simple scoring system for the prediction of early pregnancy loss (EPL) based on simple demographics. A total of 13,977 women undergoing transvaginal ultrasound scans on Days 27-29 after in vitro fertilization-embryo transfer (IVF-ET) from June 2016 and December 2017 were included. The first trimester pregnancy outcome was recorded at 12 weeks of gestation. The areas under the curve of this scoring system were 0.884 (95% confidence interval (CI) 0.870-0.899) and 0.890 (95% CI 0.878-0.903) in the training set and test set, respectively. The score totals ranged from -8 to 14 points. A score of 5 points, which offered the highest predictive accuracy (94.01%) and corresponded to a 30% miscarriage risk, was chosen as the cutoff value, with a sensitivity of 62.84%, specificity of 98.79%, positive predictive value (PPV) of 88.87% and negative predictive value (NPV) of 94.54% for the prediction of EPL in the training set. In the test set, a score of 5 points had a sensitivity of 64.69%, specificity of 98.78%, PPV of 89.87% and NPV of 93.62%, and 93.91% of the cases were correctly predicted. Therefore, the simple scoring system using conventionally collected data can be conveniently used to predict EPL after ET. However, considering the limitations, its predictive value needs to be further verified in future clinical practice.

Evaluation of a New Model for Human Chorionic Gonadotropin Rise in Pregnancies of Unknown Viability.

OBJECTIVE: To evaluate the performance of a new human chorionic gonadotropin (hCG) threshold model to classify pregnancies as viable or nonviable using a longitudinal cohort of individuals with pregnancy of unknown viability. The secondary objective was to compare the new model with three established models. METHODS: This is a single-center, retrospective cohort study of individuals seen at the University of Missouri from January 1, 2015, until March 1, 2020, who had at least two consecutive quantitative hCG serum levels with an initial level greater than 2 milli-international units/mL and 5,000 milli-international units/mL or less, with the first interval between laboratory draws no greater than 7 days. Prevalence of correct classification of viable intrauterine pregnancies, ectopic pregnancies, and early pregnancy losses was evaluated with a new proposed hCG threshold model and compared with three established models describing minimum expected rates of hCG rise for a viable intrauterine pregnancy. RESULTS: Of an initial cohort of 1,295 individuals, 688 patients met inclusion criteria. One hundred sixty-seven individuals (24.3%) had a viable intrauterine pregnancy; 463 (67.3%) had an early pregnancy loss; and 58 (8.4%) had an ectopic pregnancy. A new model based on the total additive percent rise of hCG at 4 and 6 days after initial hCG (70% or greater and 200% or greater rise, respectively) was created. The new model was able to correctly identify 100% of viable intrauterine pregnancies while minimizing incorrect classification of early pregnancy losses and ectopic pregnancies as normal pregnancies. At 4 days after initial hCG, 14 ectopic pregnancies (24.1%) and 44 early pregnancy losses (9.5%) were incorrectly classified as potentially normal pregnancies. At 6 days after initial hCG, only seven ectopic pregnancies (12.1%) and 25 early pregnancy losses (5.6%) were incorrectly classified as potentially normal pregnancies. In established models, up to nine intrauterine pregnancies (5.4%) were misclassified as abnormal pregnancies and up to 26 ectopic pregnancies (44.8%) and 58 early pregnancy losses (12.5%) were incorrectly classified as potentially normal pregnancies. CONCLUSION: The proposed new hCG threshold model optimizes a balance between identifying potentially viable intrauterine pregnancies and minimizing misdiagnosis of ectopic pregnancies and early pregnancy losses. External validation in other cohorts is needed before widespread clinical use.

Biomarkers at 6 weeks' gestation in the prediction of early miscarriage in pregnancy following assisted reproductive technology.

INTRODUCTION: Miscarriage is a major concern in early pregnancy among women having conceived with assisted reproductive treatments. This study aimed to examine potential miscarriage-related biophysical and biochemical markers at 6 weeks' gestation among women with confirmed clinical pregnancy following in vitro fertilization (IVF)/embryo transfer (ET) and evaluate the performance of a model combining maternal factors, biophysical and biochemical markers at 6 weeks' gestation in the prediction of first trimester miscarriage among singleton pregnancies following IVF/ET. MATERIAL AND METHODS: A prospective cohort study was conducted in a teaching hospital between December 2017 and January 2020 including women who conceived through IVF/ET. Maternal mean arterial pressure, ultrasound markers including mean gestational sac diameter, fetal heart activity, crown rump length and mean uterine artery pulsatility index (mUTPI) and biochemical biomarkers including maternal serum soluble fms-like tyrosine kinase-1 (sFlt-1), placental growth factor (PlGF), kisspeptin and glycodelin-A were measured at 6 weeks' gestation. Logistic regression analysis was carried out to determine significant predictors of miscarriage prior to 13 weeks' gestation and performance of screening was estimated by receiver-operating characteristics curve analysis. RESULTS: Among 169 included pregnancies, 145 (85.8%) pregnancies progressed to beyond 13 weeks' gestation and had live births whereas 24 (14.2%) pregnancies resulted in a miscarriage during the first trimester. In the miscarriage group, compared to the live birth group, maternal age, body mass index, and mean arterial pressure were significantly increased; mean gestational sac diameter, crown rump length, mUTPI, serum sFlt-1, glycodelin-A, and the rate of positive fetal heart activity were significantly decreased, while no significant differences were detected in PlGF and kisspeptin. Significant prediction for miscarriage before 13 weeks' gestation was provided by maternal age, fetal heart activity, mUTPI, and serum glycodelin-A. The combination of maternal age, ultrasound (fetal heart activity and mUTPI), and biochemical (glycodelin-A) markers achieved the highest area under the curve (AUC: 0.918, 95% CI 0.866-0.955), with estimated detection rates of 54.2% and 70.8% for miscarriage before 13 weeks' gestation, at fixed false positive rates of 5% and 10%, respectively. CONCLUSIONS: A combination of maternal age, fetal heart activity, mUTPI, and serum glycodelin-A at 6 weeks' gestation could effectively identify IVF/ET pregnancies at risk of first trimester miscarriage.