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

A simple scoring system for the prediction of early pregnancy loss developed by following 13,977 infertile patients after in vitro fertilization | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article A simple scoring system for the prediction of early pregnancy loss developed by following 13,977 infertile patients after in vitro fertilization Yan Ouyang, Senmao Zhang, Yangqin Peng, Fei Gong, Xihong Li This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-2261371/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 13 Jul, 2023 Read the published version in European Journal of Medical Research → Version 1 posted 8 You are reading this latest preprint version Abstract In order to investigate a convenient simple scoring system for the prediction of early pregnancy loss (EPL) based on simple demographics, a retrospective study with 13,977 women undergoing transvaginal ultrasound scan on Days 27–29 after in vitro fertilization-embryo transfer (IVF-ET) from June 2016 and December 2017 was conducted. The first trimester pregnancy outcome was noted 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 point -8 to 14. Points 5 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, point 5 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 routinely collected data can be conveniently used for the prediction of EPL after ET. Miscarriage early pregnancy loss in vitro fertilization-embryo transfer transvaginal sonography Introduction The first routine ultrasound scan is commonly arranged on day 28 after in vitro fertilization-embryo transfer (IVF-ET) in most reproductive centers in China to determine the location and viability of the embryo. Although the appearance of cardiac activity at first scan means a higher likelihood of ongoing pregnancy, the rate of subsequent miscarriage is between 2 and 16%[1], and there are some examples of pregnancies that were initially thought to be poorly developed but eventually developed normally[2]. Moreover, the mental and psychological pressure on women undergoing IVF-ET are significant, especially when the viability of a pregnancy is uncertain. Under these circumstances, the physician has an important role in rapidly and accurately predicting the pregnancy outcome in an evidence-based and professional manner, as this would be helpful for further consultations and in determining subsequent management. Individual maternal factors, such as a high maternal age (MA)[[3], and abnormal ultrasound parameters such as embryonic bradycardia and excessively large or small yolk sac diameter (YSD) have been shown to be associated with pregnancy failures in previous studies[4][5]. Some previous mathematical models involve combinations of individual risk factors, with reasonable performance[2][6][7][8][9]. Although these models have achieved good prediction results, they also have some shortcomings, for example, the sample size of most studies is not large enough, some study groups are mixed (mixed natural and assisted pregnancies), the gestational age (GA) is inconsistent and some studies do not give a specific probability of ongoing pregnancy or miscarriage. In addition, many patients will return to the local hospital after pregnancy. What we want to build is a model by using ultrasound data obtained from real-time measurement and simple clinical indicators such as MA, so that we can quickly predict and judge pregnancy in different hospitals without knowing many assisted fertility indicators. Therefore, the aim of this study was to investigate a convenient and accurate simple scoring system for the prediction of early pregnancy loss (EPL) based on simple demographics and the first routine ultrasound scan performed on days 27–29 after ET. Methods Participants This retrospective study was conducted at the Reproductive and Genetic Hospital of CITIC-Xiangya (Changsha, Hunan, People's Republic of China). The institutional review board approved this study (date of approval: 26 July 2019; reference number: LL-SC-2019-015; Changsha, China). The infertile patients included in this study underwent IVF treatment between June 2016 and December 2017. One to 2 embryos with good quality were transferred at the day-3 or day-5 stage. The embryo morphology was scored according to the criteria by Hardarson et al.[10]. The first routine transvaginal sonography (TVS) scan using a 5-9 MHZ probe (GE VOLUSON 730 or E8, General Electric) was arranged on days 27–29 to observe the number of embryos and their locations and viability. Only intrauterine singleton pregnancies were included. The measurements referred to the ISUOG practice guidelines [11] and conformed to uniform standards: gestational sac diameter (GSD) was calculated as the mean value of 3 perpendicular diameters with the calipers placed at the inner edges of the trophoblast; YSD was calculated as the average of 3 perpendicular diameters with the calipers placed at the center of the yolk sac (YS) wall; embryonic length (EL) was measured as the greatest length of the embryo in the anterior to posterior dimension; and embryonic heart rate (EHR) was calculated from frozen M-mode images with electronic calipers by measuring the distance between two heart waves. The presence of intrauterine hematoma (IUH), a hypoechoic or anechoic crescent-shaped area between the chorionic membrane and the myometrium, was also noted. Data on clinical characteristics including day-14 (blastocysts on day 12), serum β-human chorionic gonadotropin (HCG) levels, MA, duration of infertility, infertility type and endometrial (EM) thickness on transfer day were also collected. The first-trimester pregnancy outcomes of these participants were noted at 12 weeks of gestation. Women with a continuing pregnancy for >12 weeks of gestation were classified as ongoing pregnancy, and women with spontaneous miscarriage before or at 12 weeks of gestation were classified as EPL. Statistical analysis Categorical variables are described using frequencies, and continuous variables are described using means and standard deviations. Pearson’s chi-squared test, Fisher’s exact test, T-test or the Wilcoxon rank sum test was used to compare categorical or continuous variables between women with ongoing pregnancies and women with EPL. The cases from the first year (year 2016) were used to generate the training set, and the cases from the second year (year 2017) were used as the verification set. Binary logistic regression (LR) models were used in the training set to identify the probable predictive factors of EPL. Points associated with each category of each risk factor were computed, and the risks associated with point totals were determined according to the “The Framingham Study risk score system”[12]. Based on the area under curve (AUC) and the clinical value, we evaluated the cutoff of the prediction model which had a relatively high risk of miscarriage and high prediction accuracy. Then, we used the verification set to evaluate and verify the simple scoring system. All statistical analyses were performed using SPSS version 24.0 software (SPSS, Inc.). The results of each test were considered significant when the two-sided P value did not exceed 0.05, except where otherwise specified. Results From June 2016 to December 2017, 23,929 infertile patients obtained clinical pregnancies via IVF-ET in our hospital. 14,118 women were identified with an intrauterine singleton pregnancy during this period and among them, 141 cases were lost to follow-up. Finally, a cohort of 13,977 women were enrolled, including 12,051 cases with ongoing pregnancies and 1,926 cases with EPLs. Comparisons of women with ongoing pregnancies and EPLs Compared with women with ongoing pregnancies, the MA, body mass index, infertility duration and transfer cycle were significantly higher, and the day-14 hCG and the EM thickness on transfer day were significantly lower in women with EPLs (p < 0.001). The infertility type, cause of infertility, and insemination methods were also significantly different between women with ongoing pregnancies and EPLs (p < 0.05). The number of embryos transferred was not significantly different (p = 0.44). Based on the TVS measurements, the GSD (18.5±3.6 vs. 13.2±4.8 mm), EL (3.5±0.9 vs. 1.2±1.6 mm), YSD (3.6±0.4 vs. 2.6±1.5 mm) and EHR (114.5±2.2 vs. 42.4± 53.5 bpm) were significantly greater in women with ongoing pregnancies than those with EPLs (p < 0.001). The incidence of IUH (16.0% vs. 18.8%, P = 0.002) was also markedly higher in women with EPLs (Table 1). B inary LR analysis After stepwise screening, MA (p = 0.0001, OR 1.096, 95% confidence interval (CI) 1.073-1.119), GSD (p = 0.0001, OR 0.892, 95% CI 0.864-0.921), EL (p = 0.0020, OR 0.783, 95% CI 0.672-0.913), YSD (p = 0.0600, OR 0.853, 95% CI 0.723-1.007), EHR (p = 0.0001, OR 0.966, 95% CI 0.961-0.971) and EM on transfer day (p = 0.0030, OR 0.929, 95% CI 0.884-0.976) were found to be predictive factors of EPL and finally entered the scoring system. The scoring system The points associated with each of the categories of the risk factors were calculated and are shown in Table 2. Table 3 shows the scoring system derived from the binary LR model and the predictive value of each total point. The AUC of this scoring system was 0.884 (95% CI 0.870-0.899) in the training set. The score totals ranged from points -8 to 14. Points 5 and 6 offered the highest predictive accuracy (94.01% and 93.95%, respectively), and the predicted risks of miscarriage were 30.03% and 39.55%, respectively. Considering that IVF women were anxious, we chose point 5 corresponding to 30.03% risk of miscarriage 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 (Table 3). In the verification set, the AUC of the scoring system was 0.890 (95% CI 0.878-0.903). Point 5 had the highest diagnostic accuracy, with 93.91% of the samples correctly predicted. The sensitivity, specificity, PPV and NPV were 64.69%, 98.78%, 89.87% and 93.62%, respectively (Table 4). Discussion In this study, we collected the demographic and ultrasound findings for days 27-29 after ET and constructed a simple scoring system for the prediction of EPL, with AUCs of 0.884 and 0.878 in the training set and verification set, respectively. Point 5 had the highest predictive accuracy and was recommended as the cutoff value for clinical practice. The process of achieving pregnancy through IVF is usually very difficult for an infertile woman. Thus, when the woman becomes pregnant by IVF, she is usually very anxious about the development of the embryo, even after the detection of cardiac activity but especially if an empty gestational sac or only a YS are detected. Generally, for patients who have well-developed embryos at the first routine TVS examination on days 27-29 after ET, the next ultrasound scan will usually be scheduled on day 45 after ET; however, for patients with embryos of uncertain viability, the recommendation is usually to have another TVS scan 7-10 days after the first scan to assess the development and viability of the embryo. If the pregnancy outcome can be predicted in advance, the anxiety of the pregnant woman can be greatly relieved. Many models have been constructed to predict pregnancy outcomes effectively[13][14][15]. Among them, LR analysis has been the most commonly used[15][16]. While what we want to construct is a simple and practical scoring system that is similar to the “Apgar score system” using simple demographic and ultrasound findings on days 27–29 after ET, as this would be easy for clinical application, especially for patients without sufficient assisted reproduction indicators when they return home after pregnancy, and this is why we performed this research. Through this system, we can inform patients with a specific probability of miscarriage after the first routine TVS examination, which may help reduce the patient’s anxiety and psychological burden and provide guidance for follow-up decisions. The findings of this study agree with our current knowledge that miscarriage is more likely with increasing MA[17], low hCG level[18], low EM thickness on transfer day[19] and the presence of IUH[20] and that miscarriage is less likely after the visualization of embryonic cardiac activity[15]. Accordingly, in our scoring system, a greater MA was associated with a higher point, while greater GSD, YSD, EL and EHR were all related to lower points. However, both small and large YSDs corresponded to higher points. A higher point means a greater contribution to miscarriage. Thus, the possibility of miscarriage increased with the total score. Point 5 offered the highest predictive accuracy in both the training set and verification set, and the corresponding miscarriage risk exceeded 30%, which was not a low risk for anxious IVF patients. Therefore, we recommend using point 5 as a clinical threshold for warning patients of this risk counselled more about miscarriage. In practical applications, we hope that the false positive rate (FPR) will be as low as possible, as this may lead to unnecessary medical treatment. A low FPR requires high specificity. In this system, the specificity of points -8 to 0 was not satisfactory. Thus, this is a scoring system for determining the probability of miscarriage that could allow doctors and patients to know the risks in advance, but because miscarriage cannot be prevented, the outcome cannot be changed by this scoring system. The advantage of this scoring system is that it is easily transferable to clinical use, where both maternal and ultrasound variables are easily available and the calculation is quite easy. For example, in a woman whose MA = 38 yr and who has an EM = 8 mm on transfer day, a GSD = 10 mm, a YSD =2.2 mm, and an EHR = 88 bpm by TVS on day 28 after ET, the miscarriage score is 9, and the estimated risk of miscarriage is 70.67%. Even though the results indicate a strong likelihood of EPL, there is still a significant risk that this is a false positive finding. Thus, it is imperative to repeat the ultrasound scan for this patient 7-10 days later to confirm the viability of the embryo before any medical interventions. In contrast, if a patient does not present with any symptoms and has a low total score (for example, point 0), no TVS scan is needed until day 45 after ET. A previous study[21] constructed a similar scoring system to predict pregnancy viability and achieved an AUC of more than 0.90. However, this study focused on natural conceptions, and the ultrasound variables and clinical characteristics collected in that study were collected within a time period of GA <84 days. The measurement methods may also differ from ours. However, in our study, all ultrasound parameters were collected at the same time on days 27-29 after ET, and the specific EHR value was included, not just the presence or absence of embryonic cardiac activity. IUH was unexpectedly not included in the final system. We speculate that this may be because IUH occurs more frequently in pregnancies after IVF than in spontaneous conceptions[22], not only in women with EPLs but also with ongoing pregnancies. We note that the sensitivity of this simple model was not ideal, which might indicate that for the IVF population, only including ultrasonic measurements and simple clinical indicators had limited predictive efficacy, and in further study, relevant indicators for assisted pregnancy should be added to improve the predictive efficacy. Another limitation was that since there was no information on bleeding, abdominal pain and smoking history in our hospital's electronic medical record system during the study period, these indicators were not included in our system, but might further improve the predictive performance if included. Since this system was derived from the IVF population, its application in the general population had yet to be validated. In conclusion, we have developed a simple and practical scoring system that provides a probability for EPL based on the simple demographic and ultrasound findings obtained on days 27–29 after ET. This system is easy and simple for clinical use. Point 5 is recommended as the clinical threshold for warning patients of an EPL risk. When the predictive result is a high risk of EPL, repeated scans are recommended 7-10 days later to confirm the viability of the embryo. When the predictive result is a low risk of EPL and patients have no symptoms, the next examination can be performed on day 45 after ET. Abbreviations EPL, early pregnancy loss; IVF-ET, in vitro fertilization-embryo transfer; CI, confidence interval; PPV, positive predictive value; NPV, negative predictive value; MA, maternal age; YSD, yolk sac diameter; GA, gestational age; TVS, transvaginal sonography; GSD, gestational sac diameter; YS, yolk sac; EL, embryonic length; EHR, embryonic heart rate; IUH, intrauterine hematoma; HCG, human chorionic gonadotropin; EM, endometrium; LR, logistic regression; AUC, area under curve; FPR, false positive rate. Declarations Ethical Approval and consent to participate This study was approved by the Ethics Committee of the Reproductive and Genetic Hospital of CITIC-Xiangya (date of approval: 26 July 2019; reference number: LL-SC-2019-015; Changsha, China). Informed consent was waived due to the retrospective nature. Consent for publication Not applicable. Availability of data and material s The data analysed during this study are included in the tables. The datasets used during the current study are available from the corresponding author on reasonable request. Competing I nterests The authors have no relevant financial or non-financial interests to disclose. Funding This work was funded by the Natural Science Foundation of Hunan Province (No. 20201955), the Research Grant of CITIC-Xiangya (No. YNXM-202220) and the Science and Technology Project of the Health, Family Planning Commission of Hunan Province (No. C20180289). Authors’ contributions XL and YO designed the study and all authors contributed to the study’s conception and design. Material preparation and data collection were performed by FG and YO. Data analysis were performed by SZ and YP. The first draft of the manuscript was written by YO. All authors read and approved the final manuscript. Acknowledgements The authors thank Qingqing Wu and Mingxiang Zheng for their help in data collection. References Rull K, Laan M (2005) Expression of β-subunit of HCG genes during normal and failed pregnancy. Hum Reprod. https://doi.org/10.1093/humrep/dei261 Yi Y, Li X, Ouyang Y, et al (2016) Discriminant analysis forecasting model of first trimester pregnancy outcomes developed by following 9,963 infertile patients after in vitro fertilization Abstract has been accepted for oral presentation (O-222) at the 71th America Society of Reproductive. 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Aust New Zeal J Obstet Gynaecol. https://doi.org/10.1111/ajo.12395 Casikar I, Lu C, Reid S, Condous G (2013) Prediction of successful expectant management of first trimester miscarriage: Development and validation of a new mathematical model. Aust New Zeal J Obstet Gynaecol. https://doi.org/10.1111/ajo.12053 Shaamash AH, Aly HA, Abdel-Aleem M, Akhnowkh SN (2020) Clinical and Ultrasound Evaluation of Early Threatened Miscarriage to Predict Pregnancy Continuation up to 28 Weeks : A Prospective Cohort Study. J Ultrasound Med. https://doi.org/10.1002/jum.15282 Wang XH, Wang HJ, Deng XH, et al (2019) Predictive value of ultrasound-related scoring system on embryo development in early pregnancy after IVF/ICSI: An observation of embryonic quality. Taiwan J Obstet Gynecol. https://doi.org/10.1016/j.tjog.2019.05.013 Yi Y, Lu G, Ouyang Y, et al (2016) A logistic model to predict early pregnancy loss following in vitro fertilization based on 2601 infertility patients. Reprod Biol Endocrinol 14:. https://doi.org/10.1186/s12958-016-0147-z Salomon LJ, Alfirevic Z, Bilardo CM, et al (2013) Erratum: ISUOG practice guidelines: Performance of first-trimester fetal ultrasound scan. Ultrasound Obstet Gynecol 2013; 41: 102-113. DOI: 10.1002/uog.12342. Ultrasound Obstet. Gynecol. Hardarson T, Hanson C, Sjögren a, Lundin K (2001) Human embryos with unevenly sized blastomeres have lower pregnancy and implantation rates: indications for aneuploidy and multinucleation. Hum Reprod 16:313–318. https://doi.org/10.1093/humrep/16.2.313 Sullivan LM, Massaro JM, D’Agostino RB (2004) Presentation of multivariate data for clinical use: The Framingham Study risk score functions. Stat Med. https://doi.org/10.1002/sim.1742 Bottomley C, Van Belle V, Pexsters A, et al (2011) A model and scoring system to predict outcome of intrauterine pregnancies of uncertain viability. Ultrasound Obstet Gynecol. https://doi.org/10.1002/uog.9007 Guha S, Van Belle V, Bottomley C, et al (2013) External validation of models and simple scoring systems to predict miscarriage in intrauterine pregnancies of uncertain viability. Hum Reprod. https://doi.org/10.1093/humrep/det342 Lautmann K, Cordina M, Elson J, et al (2011) Clinical use of a model to predict the viability of early intrauterine pregnancies when no embryo is visible on ultrasound. Hum Reprod. https://doi.org/10.1093/humrep/der287 Khalil A, Syngelaki A, Maiz N, et al (2013) Maternal age and adverse pregnancy outcome: A cohort study. Ultrasound Obstet Gynecol. https://doi.org/10.1002/uog.12494 Pillai RN, Konje JC, Tincello DG, Potdar N (2016) Role of serum biomarkers in the prediction of outcome in women with threatened miscarriage: A systematic review and diagnostic accuracy meta-analysis. Hum. Reprod. Update Kasius A, Smit JG, Torrance HL, et al (2014) Endometrial thickness and pregnancy rates after IVF: A systematic review and meta-analysis. Hum Reprod Update. https://doi.org/10.1093/humupd/dmu011 Tuuli MG, Norman SM, Odibo AO, et al (2011) Perinatal outcomes in women with subchorionic hematoma: A systematic review and meta-analysis. Obstet. Gynecol. Bottomley C, Van Belle V, Kirk E, et al (2013) Accurate prediction of pregnancy viability by means of a simple scoring system. Hum Reprod. https://doi.org/10.1093/humrep/des352 Asato K, Mekaru K, Heshiki C, et al (2014) Subchorionic hematoma occurs more frequently in in vitro fertilization pregnancy. Eur J Obstet Gynecol Reprod Biol. https://doi.org/10.1016/j.ejogrb.2014.07.014 Tables Table 1 Comparisons of the parameters between 2 groups Parameter Ongoing pregnancy (12,051) Early pregnancy loss (1,926) P OR （ 95% CI ） Maternal age (years) 30.9±4.5 33.3±5.4 <0.001 BMI(kg/m2) 21.8±2.4 22.1±2.6 <0.001 Infertility duration (years) 4.0±3.0 4.4±3.6 0.001 Transfer cycle 1.2±0.7 1.4±0.8 <0.001 Infertility type Primary 4673 (38.78%) 602 (31.26%) <0.001 1.393（1.257-1.544） Secondary 7378 (61.22%) 1324 (68.74%) Cause of infertility Male 831 (6.90%) 112 (5.82%) 0.014 Female 6920 (57.42%) 1176 (61.06%) Combined male and female 3764 (31.23%) 550 (28.56%) Unexlained 536 (4.45%) 88 (4.57%) 14-day HCG (mIU/ml) 594.4±301.7 430.5±283.9 <0.001 EM thickness on transfer 12.6±2.0 12.3±1.9 <0.001 Insemination methods IVF 5584 (46.34%) 829 (43.06%) <0.001 ICSI 2081 (17.27%) 293 (15.22%) IVF/ICSI 4386 (36.40%) 804 (41.72%) Number of embryos transferred 1.7±0.5 1.7±0.5 0.44NS Intrauterine hematomas Presence 1928 (16.00%) 363 (18.85%) 0.002 0.820（0.724-0.928） Absence 10123 (84.00%) 1563 (81.15%) GSD (mm) 18.5±3.6 13.2±4.8 <0.001 YSD (mm) 3.6±0.4 2.6±1.5 <0.001 CRL (mm) 3.5±0.9 1.2±1.6 <0.001 EHR (bpm) 114.5±12.2 42.4±53.5 <0.001 Note: NS =not significant.OR=odds ratio; CI = confidence interval;BMI = body mass index;HCG = human chorionic gonadotropin; EM= endometrium; IVF = in vitro fertilization; ICSI = intracytoplasmic sperm injection;GSD = gestational sac diameter； YSD = yolk sac diameter;CRL= crown-rump length; EHR = embryonic heart rate. Table 2 Points associated with each of the categories of the risk factors Variable Reference value (W ij ) β i Β i (W ij -W iREF ) Points MA (years) 0.0920 <29 26.00 -0.78 -2 30-39 34.50=W 1REF 0.00 0 ≥40 42.00 0.69 2 GSD (mm) -0.1150 27.0 27.30 -0.95 -2 CRL (mm) -0.2450 6.3 6.50 -0.56 -1 EHR (mm) -0.0340 <100 50.00 2.21 5 100-130 115.00=W 4REF 0.00 0 ≥130 140.00 -0.85 -2 YSD (mm) -0.1590 <3.00 1.50 0.40 1 3.00~4.99 4.00=W 5REF 0.00 0 ≥5.00 6.00 0.32 1 EM (mm) -0.074 <10.0 5.00 0.56 1 10-14.99 12.50=W 6REF 0.00 0 ≥15.00 16.30 -0.28 -1 Points=βi (Wij-WiREF)/B B=5*0.0920 Note: MA = maternal age; GSD = gestational sac diameter；CRL= crown-rump length; EHR = embryonic heart rate;YSD = yolk sac diameter; EM = endometrium. Table 3 Scoring system derived from the binary LR model. Sum of points Estimated risk of miscarriage (%) Sensitivity (%) Specificity (%) PPV (%) NPV (%) ACC (%) -8 0.18% 100.00% 0.00% 13.30% - 13.30% -7 0.24% 100.00% 0.00% 13.30% - 13.30% -6 0.31% 100.00% 0.00% 13.30% - 13.30% -5 0.54% 100.00% 0.00% 13.30% - 13.30% -4 0.81% 100.00% 0.11% 13.32% 100.00% 13.40% -3 1.24% 99.69% 0.79% 13.36% 94.34% 13.95% -2 1.85% 99.28% 5.32% 13.86% 97.95% 17.82% -1 2.84% 93.89% 34.88% 18.12% 97.38% 42.74% 0 4.20% 91.72% 46.37% 20.79% 97.33% 52.40% 1 7.33% 80.23% 83.80% 43.18% 96.51% 83.32% 2 11.02% 75.98% 91.74% 58.53% 96.14% 89.64% 3 15.57% 70.91% 96.22% 74.21% 95.57% 92.85% 4 22.03% 68.01% 97.55% 81.01% 95.21% 93.62% 5 30.03% 62.84% 98.79% 88.87% 94.54% 94.01% 6 39.55% 66.87% 98.11% 84.44% 95.07% 93.95% 7 50.59% 57.04% 99.02% 89.89% 93.76% 93.43% 8 60.50% 49.48% 99.41% 92.82% 92.77% 92.77% 9 70.67% 39.13% 99.57% 93.33% 91.42% 91.53% 10 78.54% 26.71% 99.83% 95.91% 89.87% 90.10% 11 84.90% 15.63% 99.92% 96.79% 88.53% 88.71% 12 89.51% 6.11% 99.95% 95.16% 87.40% 87.47% 13 92.65% 3.00% 100.00% 100.00% 87.04% 87.10% 14 95.42% 0.52% 100.00% 100.00% 86.76% 86.76% Note: LR = logistic regression; PPV = positive predictive value; NPV= negative predictive value; ACC = accuracy. Table 4 The classification of the results obtained using point 5 as the cutoff value Scoring system Training samples EPL Ongoing pregnancy Total EPL(n) 607 359 966 Ongoing pregnancy 76 6219 6295 EPL(%) 62.84% 37.16% 100.00% Ongoing pregnancy(%) 1.21% 98.79% 100.00% Verification sample EPL(n) 621 339 960 Ongoing pregnancy(n) 70 5686 5756 EPL(%) 64.69% 35.31% 100.00% Ongoing pregnancy(%) 1.22% 98.78% 100.00% Note: EPL: early pregnancy loss Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 13 Jul, 2023 Read the published version in European Journal of Medical Research → Version 1 posted Editorial decision: Major revision 08 May, 2023 Reviews received at journal 23 Apr, 2023 Reviewers agreed at journal 21 Feb, 2023 Reviewers agreed at journal 21 Feb, 2023 Reviewers invited by journal 18 Feb, 2023 Editor assigned by journal 16 Feb, 2023 Submission checks completed at journal 14 Nov, 2022 First submitted to journal 10 Nov, 2022 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-2261371","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":151835209,"identity":"115b1fe3-aa08-40b5-b160-fc6e0469fe35","order_by":0,"name":"Yan Ouyang","email":"","orcid":"","institution":"Reproductive and Genetic Hospital of CITIC-Xiangya","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yan","middleName":"","lastName":"Ouyang","suffix":""},{"id":151835210,"identity":"eb7e30d9-3fe1-45cc-aa0b-4386a20e2c18","order_by":1,"name":"Senmao Zhang","email":"","orcid":"","institution":"Central South University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Senmao","middleName":"","lastName":"Zhang","suffix":""},{"id":151835211,"identity":"00bd8e7c-6d47-4824-bbc1-16d33f3c3109","order_by":2,"name":"Yangqin Peng","email":"","orcid":"","institution":"Reproductive and Genetic Hospital of CITIC-Xiangya","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yangqin","middleName":"","lastName":"Peng","suffix":""},{"id":151835213,"identity":"654042d7-c574-4fd2-8e0d-ccfc73640429","order_by":3,"name":"Fei Gong","email":"","orcid":"","institution":"Reproductive and Genetic Hospital of CITIC-Xiangya","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Fei","middleName":"","lastName":"Gong","suffix":""},{"id":151835215,"identity":"67440937-e4ff-43ab-b8de-166f6600f94d","order_by":4,"name":"Xihong Li","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA4UlEQVRIiWNgGAWjYDACZh4QaQEk2RgfJFTUEK1FAqSF2eDBmWPEWAPRAsRsbJIPW5gJazA4znvwccEvCRmDG2lpFYkNbAz87d0JeLVINvMlG8/sk+AxOHPs2I3EHTIMEmfObsCrhZ+Zx0yatweo5Xh7243EM2wMBhK5+LWwwbUcZm8rSGxjJqwFbAvPD5AtbccYiNIi2cxjbMzbIMEjeeZYskTCmWM8BP1icP6M4WOePzb2fDfSDD/+qKiR42/vxa8FDBjbGBgUDkDYPISVg8EfBgb5BiLVjoJRMApGwcgDAM9zQcMVhMqQAAAAAElFTkSuQmCC","orcid":"","institution":"Reproductive and Genetic Hospital of CITIC-Xiangya","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Xihong","middleName":"","lastName":"Li","suffix":""}],"badges":[],"createdAt":"2022-11-11 03:29:08","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-2261371/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-2261371/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s40001-023-01218-z","type":"published","date":"2023-07-14T01:08:02+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":41742670,"identity":"9302092b-0fde-4add-97f3-99a08ad2d883","added_by":"auto","created_at":"2023-08-18 04:36:14","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":288024,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-2261371/v1/88f21864-c0ef-49b4-914d-77e4481452e1.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"A simple scoring system for the prediction of early pregnancy loss developed by following 13,977 infertile patients after in vitro fertilization","fulltext":[{"header":"Introduction","content":"\u003cp\u003eThe first routine ultrasound scan is commonly arranged on day 28 after in vitro\u0026nbsp;fertilization-embryo transfer (IVF-ET) in most reproductive centers in China to\u0026nbsp;determine the location and viability of the embryo. Although the appearance of\u0026nbsp;cardiac activity at first scan means a higher likelihood of ongoing pregnancy, the rate\u0026nbsp;of subsequent miscarriage is between 2 and 16%[1], and there are some examples of\u0026nbsp;pregnancies that were initially thought to be poorly developed but eventually\u0026nbsp;developed normally[2]. Moreover, the mental and psychological pressure on women\u0026nbsp;undergoing IVF-ET are significant,\u0026nbsp;especially when the viability of a pregnancy is\u0026nbsp;uncertain. Under these circumstances, the physician has an important role in rapidly\u0026nbsp;and accurately predicting the pregnancy outcome in an evidence-based and\u0026nbsp;professional manner, as this would be helpful for further consultations and in\u0026nbsp;determining subsequent management.\u003c/p\u003e\n\u003cp\u003eIndividual maternal factors, such as a high maternal age (MA)[[3], and abnormal\u0026nbsp;ultrasound parameters such as embryonic bradycardia and excessively large or small\u0026nbsp;yolk sac diameter (YSD) have been shown to be associated with pregnancy failures in\u0026nbsp;previous studies[4][5]. Some previous mathematical models involve combinations of\u0026nbsp;individual risk factors, with reasonable performance[2][6][7][8][9].\u0026nbsp;Although these models have achieved good prediction results, they also have some shortcomings, for example, the sample size of most studies is not large enough, some study groups are mixed (mixed natural and assisted pregnancies), the gestational age (GA) is inconsistent and some studies do not give a specific probability of ongoing pregnancy or miscarriage. In addition, many patients will return to the local hospital after pregnancy. What we want to build is a model by using ultrasound data obtained from real-time measurement and simple clinical indicators such as MA, so that we can quickly predict and judge pregnancy in different hospitals without knowing many assisted fertility indicators.\u003c/p\u003e\n\u003cp\u003eTherefore, the aim of this study was to investigate a convenient and accurate simple scoring system for the prediction of early pregnancy loss (EPL) based on simple demographics and the first routine ultrasound scan performed on days 27\u0026ndash;29 after ET.\u0026nbsp;\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e\u003cstrong\u003eParticipants\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis retrospective study was conducted at the Reproductive and Genetic Hospital of CITIC-Xiangya (Changsha, Hunan, People\u0026apos;s Republic of China). The institutional review board approved this study\u0026nbsp;(date of approval: 26 July 2019; reference number: LL-SC-2019-015; Changsha, China).\u003c/p\u003e\n\u003cp\u003eThe infertile patients included in this study underwent IVF treatment between June 2016 and December 2017. One to 2 embryos with good quality were transferred at the day-3 or day-5 stage. The embryo morphology was scored according to the criteria by Hardarson et al.[10]. The first routine transvaginal sonography (TVS) scan using a 5-9 MHZ probe (GE VOLUSON 730 or E8, General Electric) was arranged on days 27\u0026ndash;29 to observe the number of embryos and their locations and viability.\u0026nbsp;Only\u0026nbsp;intrauterine singleton pregnancies were included.\u0026nbsp;The measurements referred to the ISUOG practice guidelines\u0026nbsp;[11]\u0026nbsp;and conformed to uniform standards: gestational sac diameter (GSD) was calculated as the mean value of 3 perpendicular diameters with the calipers placed at the inner edges of the trophoblast; YSD was calculated as the average of 3 perpendicular diameters with the calipers placed at the center of the yolk sac (YS) wall; embryonic length (EL) was measured as the greatest length of the embryo in the anterior to posterior dimension; and embryonic heart rate (EHR) was calculated from frozen M-mode images with electronic calipers by measuring the distance between two heart waves. The presence of intrauterine hematoma (IUH), a hypoechoic or anechoic crescent-shaped area between the chorionic membrane and the myometrium, was also noted. Data on clinical characteristics including day-14 (blastocysts on day 12), serum \u0026beta;-human chorionic gonadotropin (HCG) levels, MA, duration of infertility, infertility type and endometrial (EM) thickness on transfer day were also collected. The first-trimester pregnancy outcomes of these participants were noted at 12 weeks of gestation. Women with\u0026nbsp;a\u0026nbsp;continuing\u0026nbsp;pregnancy for \u0026gt;12 weeks of gestation were\u0026nbsp;classified as\u0026nbsp;ongoing pregnancy, and women with spontaneous miscarriage before or at 12 weeks of gestation were\u0026nbsp;classified as\u0026nbsp;EPL.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCategorical variables are described using frequencies, and continuous variables are described using means and standard deviations. Pearson\u0026rsquo;s chi-squared test, Fisher\u0026rsquo;s exact test, T-test or the Wilcoxon rank sum test was used to compare categorical or continuous variables between women with ongoing pregnancies and women with EPL. The cases from the first year (year 2016) were used to generate the training set, and the cases from the second year (year 2017) were used as the verification set. Binary logistic regression (LR) models were used in the training set to identify the probable predictive factors of EPL. Points associated with each category of each risk factor were computed, and the risks associated with point totals were determined according to the \u0026ldquo;The Framingham Study risk score system\u0026rdquo;[12]. Based on the area under curve (AUC) and the clinical value, we evaluated the cutoff of the prediction model which had a relatively high risk of miscarriage and high prediction accuracy. Then, we used the verification set to evaluate and verify the simple scoring system. All statistical analyses were performed using SPSS version 24.0 software (SPSS, Inc.). The results of each test were considered significant when the two-sided P value did not exceed 0.05, except where otherwise specified.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eFrom June 2016 to December 2017, 23,929 infertile patients obtained clinical\u0026nbsp;pregnancies via IVF-ET in our hospital. 14,118 women were identified with an\u0026nbsp;intrauterine singleton pregnancy during this period and among them, 141 cases were\u0026nbsp;lost to follow-up. Finally, a cohort of 13,977 women were enrolled, including 12,051\u0026nbsp;cases\u0026nbsp;with\u0026nbsp;ongoing pregnancies\u0026nbsp;and 1,926 cases\u0026nbsp;with\u0026nbsp;EPLs.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eComparisons of\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003ewomen with ongoing pregnancies and EPLs\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCompared with\u0026nbsp;women with\u0026nbsp;ongoing pregnancies, the MA, body mass index,\u0026nbsp;infertility duration and transfer cycle were significantly higher, and the day-14 hCG\u0026nbsp;and the EM thickness on transfer day were significantly lower in\u0026nbsp;women with\u0026nbsp;EPLs\u0026nbsp;(p \u0026lt;\u0026nbsp;0.001). The infertility type, cause of infertility, and insemination methods were also\u0026nbsp;significantly different between\u0026nbsp;women with\u0026nbsp;ongoing pregnancies and EPLs\u0026nbsp;(p \u0026lt; 0.05). The number of embryos\u0026nbsp;transferred was not significantly different (p = 0.44).\u003c/p\u003e\n\u003cp\u003eBased on the TVS measurements, the GSD (18.5\u0026plusmn;3.6 vs. 13.2\u0026plusmn;4.8 mm), EL\u0026nbsp;(3.5\u0026plusmn;0.9 vs. 1.2\u0026plusmn;1.6 mm), YSD (3.6\u0026plusmn;0.4 vs. 2.6\u0026plusmn;1.5 mm) and EHR (114.5\u0026plusmn;2.2 vs.\u0026nbsp;42.4\u0026plusmn;\u0026nbsp;53.5 bpm) were significantly greater in\u0026nbsp;women with\u0026nbsp;ongoing pregnancies\u0026nbsp;than those\u0026nbsp;with\u0026nbsp;EPLs\u0026nbsp;(p \u0026lt; 0.001). The incidence\u0026nbsp;of IUH (16.0% vs. 18.8%, P = 0.002)\u0026nbsp;was also markedly higher in\u0026nbsp;women with\u0026nbsp;EPLs\u0026nbsp;(Table 1).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eB\u003c/strong\u003e\u003cstrong\u003einary\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;LR analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAfter stepwise screening, MA (p =\u0026nbsp;0.0001, OR 1.096,\u0026nbsp;95% confidence interval (CI)\u0026nbsp;1.073-1.119), GSD (p =\u0026nbsp;0.0001, OR 0.892, 95% CI 0.864-0.921), EL (p =\u0026nbsp;0.0020, OR\u0026nbsp;0.783, 95% CI 0.672-0.913), YSD (p = 0.0600, OR 0.853, 95% CI 0.723-1.007), EHR\u0026nbsp;(p =\u0026nbsp;0.0001, OR 0.966, 95% CI 0.961-0.971) and EM on transfer day (p =\u0026nbsp;0.0030, OR\u0026nbsp;0.929, 95% CI 0.884-0.976) were found to be predictive factors of EPL and finally\u0026nbsp;entered the scoring system.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eThe scoring system\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe points\u0026nbsp;associated with each of the categories of the risk factors were calculated\u0026nbsp;and are shown in Table 2. Table 3 shows the scoring system derived from the\u0026nbsp;binary\u0026nbsp;LR model and the predictive value of each total point. The AUC of\u0026nbsp;this\u0026nbsp;scoring system was 0.884 (95% CI 0.870-0.899) in the training set. The score totals\u0026nbsp;ranged from points -8 to 14. Points 5 and 6 offered the highest predictive accuracy\u0026nbsp;(94.01% and 93.95%, respectively), and the predicted risks of miscarriage were 30.03%\u0026nbsp;and 39.55%, respectively.\u0026nbsp;Considering that IVF women were anxious, we chose point\u0026nbsp;5 corresponding to 30.03% risk of miscarriage as the cutoff value, with a sensitivity of\u0026nbsp;62.84%, specificity of 98.79%, positive predictive value (PPV) of 88.87% and\u0026nbsp;negative predictive value (NPV) of 94.54%, for the prediction of EPL in the training\u0026nbsp;set\u0026nbsp;(Table 3).\u003c/p\u003e\n\u003cp\u003eIn the verification set, the AUC of the scoring system was 0.890 (95% CI 0.878-0.903). Point 5 had the highest diagnostic accuracy, with 93.91% of the samples correctly predicted. The sensitivity, specificity, PPV and NPV were 64.69%, 98.78%, 89.87% and 93.62%, respectively (Table 4).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this study, we collected the demographic and ultrasound findings for days 27-29\u0026nbsp;after ET and constructed a simple scoring system for the prediction of EPL, with\u0026nbsp;AUCs of 0.884 and 0.878 in the training set and verification set, respectively. Point 5\u0026nbsp;had the highest predictive accuracy and was recommended as the cutoff value for\u0026nbsp;clinical practice.\u003c/p\u003e\n\u003cp\u003eThe process of achieving pregnancy through IVF is usually very difficult for an\u0026nbsp;infertile woman. Thus, when the woman becomes pregnant by IVF, she is usually\u0026nbsp;very anxious about the development of the embryo, even after the detection of cardiac\u0026nbsp;activity but especially if an empty gestational sac or only a YS are detected. Generally,\u0026nbsp;for patients who have well-developed embryos at the first routine TVS examination\u0026nbsp;on days 27-29 after ET, the next ultrasound scan will usually be scheduled on day 45\u0026nbsp;after ET; however, for patients with embryos of uncertain viability, the\u0026nbsp;recommendation is usually to have another TVS scan 7-10 days after the first scan to\u0026nbsp;assess the development and viability of the embryo.\u003c/p\u003e\n\u003cp\u003eIf the pregnancy outcome can be predicted in advance, the anxiety of the pregnant\u0026nbsp;woman can be greatly relieved. Many models have been constructed to predict\u0026nbsp;pregnancy outcomes effectively[13][14][15]. Among them, LR analysis has been the\u0026nbsp;most commonly used[15][16].\u0026nbsp;While what we want to construct is a simple and practical\u0026nbsp;scoring system that is similar to the \u0026ldquo;Apgar score system\u0026rdquo;\u0026nbsp;using simple\u0026nbsp;demographic and ultrasound findings\u0026nbsp;on days 27\u0026ndash;29 after ET, as this would be easy for clinical application, especially for patients without sufficient\u0026nbsp;assisted reproduction\u0026nbsp;indicators when they return home after pregnancy, and this is why we performed this research. Through this\u0026nbsp;system, we can inform patients with a specific probability of miscarriage after the first\u0026nbsp;routine TVS examination, which may help reduce the patient\u0026rsquo;s anxiety and\u0026nbsp;psychological burden and provide guidance for follow-up decisions.\u003c/p\u003e\n\u003cp\u003eThe findings of this study agree with our current knowledge that miscarriage is\u0026nbsp;more likely with increasing MA[17], low hCG level[18], low EM thickness on\u0026nbsp;transfer day[19]\u0026nbsp;and the presence of IUH[20]\u0026nbsp;and that miscarriage is less likely after\u0026nbsp;the visualization of embryonic cardiac activity[15]. Accordingly, in our scoring\u0026nbsp;system, a greater MA was associated with a higher point, while greater GSD, YSD,\u0026nbsp;EL and EHR were all related to lower points. However, both small and large YSDs\u0026nbsp;corresponded to higher points. A higher point means a greater contribution to\u0026nbsp;miscarriage. Thus, the possibility of miscarriage increased with the total score. Point 5\u0026nbsp;offered the highest predictive accuracy in both the training set and verification set,\u0026nbsp;and the corresponding miscarriage risk exceeded 30%, which was not a low risk for\u0026nbsp;anxious IVF patients. Therefore, we recommend using point 5 as a clinical threshold for warning patients of this risk \u0026nbsp;counselled more about miscarriage.\u0026nbsp;In practical\u0026nbsp;applications, we hope that the false positive rate (FPR) will be as low as possible, as\u0026nbsp;this may lead to unnecessary medical treatment. A low FPR requires high specificity.\u0026nbsp;In this system, the specificity of points -8\u0026nbsp;to\u0026nbsp;0 was not satisfactory. Thus, this is a\u0026nbsp;scoring system for determining the probability of miscarriage that could allow doctors\u0026nbsp;and patients to know the risks in advance, but because miscarriage cannot be\u0026nbsp;prevented, the outcome cannot be changed by this scoring system.\u0026nbsp;The advantage of this scoring system is that it is easily transferable to clinical use,\u0026nbsp;where both maternal and ultrasound variables are easily available and the calculation is quite easy. For example, in a woman whose MA = 38 yr and who has an EM = 8 mm on transfer day, a GSD = 10 mm, a YSD =2.2 mm, and an EHR = 88 bpm by TVS on day 28 after ET, the miscarriage score is 9, and the estimated risk of miscarriage is 70.67%. Even though the results indicate a strong likelihood of EPL, there is still a significant risk that this is a false positive finding. Thus, it is imperative to repeat the ultrasound scan for this patient 7-10 days later to confirm the viability of the embryo before any medical interventions. In contrast, if a patient does not present with any symptoms and has a low total score (for example, point 0), no TVS scan is needed until day 45 after ET.\u003c/p\u003e\n\u003cp\u003eA previous study[21]\u0026nbsp;constructed a similar scoring system to predict pregnancy\u0026nbsp;viability and achieved an AUC of more than 0.90. However, this study focused on\u0026nbsp;natural conceptions, and the ultrasound variables and clinical characteristics collected\u0026nbsp;in that study were collected\u0026nbsp;within a time period of GA \u0026lt;84\u0026nbsp;days. The measurement methods may also differ from ours. However, in our study, all\u0026nbsp;ultrasound parameters were collected at the same time on days 27-29 after ET, and the\u0026nbsp;specific EHR value was included, not just the presence or absence of embryonic\u0026nbsp;cardiac activity. IUH was unexpectedly not included in the final system. We speculate\u0026nbsp;that this may be because IUH occurs more frequently\u0026nbsp;in pregnancies after IVF than in\u0026nbsp;spontaneous conceptions[22],\u0026nbsp;not only in\u0026nbsp;women with\u0026nbsp;EPLs\u0026nbsp;but also\u0026nbsp;with\u0026nbsp;ongoing\u0026nbsp;pregnancies.\u003c/p\u003e\n\u003cp\u003eWe note that the sensitivity of this simple model\u0026nbsp;was\u0026nbsp;not ideal, which might\u0026nbsp;indicate that for\u0026nbsp;the\u0026nbsp;IVF population, only including ultrasonic measurements and simple clinical indicators had\u0026nbsp;limited predictive efficacy, and\u0026nbsp;in further study,\u0026nbsp;relevant indicators for assisted pregnancy\u0026nbsp;should\u0026nbsp;be added to improve the predictive efficacy.\u0026nbsp;Another limitation was that\u0026nbsp;since there\u0026nbsp;was no information on bleeding, abdominal pain and smoking history in our hospital\u0026apos;s electronic medical record system\u0026nbsp;during the study period, these indicators\u0026nbsp;were not included in our\u0026nbsp;system,\u0026nbsp;but might further improve the\u0026nbsp;predictive performance if included. Since this system\u0026nbsp;was\u0026nbsp;derived from the IVF population, its application in the general population had\u0026nbsp;yet to be validated.\u003c/p\u003e\n\u003cp\u003eIn conclusion, we have developed a simple and practical scoring system that \u0026nbsp;provides a probability for EPL based on the simple demographic and ultrasound findings obtained on days 27\u0026ndash;29 after ET. This system is easy and simple for clinical use. Point 5 is recommended as the clinical threshold for warning patients of an EPL risk. When the predictive result is a high risk of EPL, repeated scans are recommended 7-10 days later to confirm the viability of the embryo. When the predictive result is a low risk of EPL and patients have no symptoms, the next examination can be performed on day 45 after ET.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eEPL,\u0026nbsp;early pregnancy loss;\u0026nbsp;IVF-ET,\u0026nbsp;in vitro fertilization-embryo transfer;\u0026nbsp;CI, \u0026nbsp;confidence interval;\u0026nbsp;PPV,\u0026nbsp;positive predictive value;\u0026nbsp;NPV,\u0026nbsp;negative predictive value;\u0026nbsp;MA,\u0026nbsp;maternal age;\u0026nbsp;YSD,\u0026nbsp;yolk sac diameter;\u0026nbsp;GA,\u0026nbsp;gestational age;\u0026nbsp;TVS,\u0026nbsp;transvaginal sonography;\u0026nbsp;GSD,\u0026nbsp;gestational sac diameter;\u0026nbsp;YS,\u0026nbsp;yolk sac;\u0026nbsp;EL,\u0026nbsp;embryonic length;\u0026nbsp;EHR,\u0026nbsp;embryonic heart rate;\u0026nbsp;IUH,\u0026nbsp;intrauterine hematoma;\u0026nbsp;HCG,\u0026nbsp;human chorionic gonadotropin;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eEM, endometrium; LR, logistic regression; AUC, area under curve; FPR, false positive rate.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthical Approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was approved by the Ethics Committee of the Reproductive and Genetic Hospital of CITIC-Xiangya\u0026nbsp;(date of approval: 26 July 2019; reference number: LL-SC-2019-015; Changsha, China).\u0026nbsp;Informed consent was waived due to the retrospective nature.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and material\u003c/strong\u003e\u003cstrong\u003es\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe data analysed during this study are included in the tables. The datasets used during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eI\u003c/strong\u003e\u003cstrong\u003enterests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors have no relevant financial or non-financial interests to disclose.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was funded by the Natural Science Foundation of Hunan Province (No. 20201955),\u0026nbsp;the Research Grant of CITIC-Xiangya (No. YNXM-202220)\u0026nbsp;and the Science and Technology Project of the Health, Family Planning Commission of Hunan Province (No. C20180289).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions \u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eXL and YO designed the study\u0026nbsp;and all\u0026nbsp;authors contributed to the study\u0026rsquo;s conception and design. Material preparation\u0026nbsp;and\u0026nbsp;data collection\u0026nbsp;were performed by\u0026nbsp;FG and YO. Data\u0026nbsp;analysis were performed by\u0026nbsp;SZ and YP.\u0026nbsp;The first draft of the manuscript was written by\u0026nbsp;YO. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors thank Qingqing Wu and Mingxiang Zheng for their help in data collection.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eRull K, Laan M (2005) Expression of \u0026beta;-subunit of HCG genes during normal and failed pregnancy. Hum Reprod. https://doi.org/10.1093/humrep/dei261\u003c/li\u003e\n \u003cli\u003eYi Y, Li X, Ouyang Y, et al (2016) Discriminant analysis forecasting model of first trimester pregnancy outcomes developed by following 9,963 infertile patients after in vitro fertilization Abstract has been accepted for oral presentation (O-222) at the 71th America Society of Reproductive. Fertil Steril 105:. https://doi.org/10.1016/j.fertnstert.2016.01.033\u003c/li\u003e\n \u003cli\u003eEvaluation and treatment of recurrent pregnancy loss: A committee opinion. Fertil Steril. https://doi.org/10.1016/j.fertnstert.2012.06.048\u003c/li\u003e\n \u003cli\u003eMorin L, Cargill YM, Glanc P (2016) Ultrasound Evaluation of First Trimester Complications of Pregnancy. J Obstet Gynaecol Canada. https://doi.org/10.1016/j.jogc.2016.06.001\u003c/li\u003e\n \u003cli\u003eSpencer K, Cowans NJ, Avgidou K, Nicolaides KH (2006) First-trimester ultrasound and biochemical markers of aneuploidy and the prediction of impending fetal death. Ultrasound Obstet Gynecol. https://doi.org/10.1002/uog.3809\u003c/li\u003e\n \u003cli\u003eStamatopoulos N, Lu C, Casikar I, et al (2015) Prediction of subsequent miscarriage risk in women who present with a viable pregnancy at the first early pregnancy scan. Aust New Zeal J Obstet Gynaecol. https://doi.org/10.1111/ajo.12395\u003c/li\u003e\n \u003cli\u003eCasikar I, Lu C, Reid S, Condous G (2013) Prediction of successful expectant management of first trimester miscarriage: Development and validation of a new mathematical model. Aust New Zeal J Obstet Gynaecol. https://doi.org/10.1111/ajo.12053\u003c/li\u003e\n \u003cli\u003eShaamash AH, Aly HA, Abdel-Aleem M, Akhnowkh SN (2020) Clinical and Ultrasound Evaluation of Early Threatened Miscarriage to Predict Pregnancy Continuation up to 28 Weeks : A Prospective Cohort Study. J Ultrasound Med. https://doi.org/10.1002/jum.15282\u003c/li\u003e\n \u003cli\u003eWang XH, Wang HJ, Deng XH, et al (2019) Predictive value of ultrasound-related scoring system on embryo development in early pregnancy after IVF/ICSI: An observation of embryonic quality. Taiwan J Obstet Gynecol. https://doi.org/10.1016/j.tjog.2019.05.013\u003c/li\u003e\n \u003cli\u003eYi Y, Lu G, Ouyang Y, et al (2016) A logistic model to predict early pregnancy loss following in vitro fertilization based on 2601 infertility patients. Reprod Biol Endocrinol 14:. https://doi.org/10.1186/s12958-016-0147-z\u003c/li\u003e\n \u003cli\u003eSalomon LJ, Alfirevic Z, Bilardo CM, et al (2013) Erratum: ISUOG practice guidelines: Performance of first-trimester fetal ultrasound scan. Ultrasound Obstet Gynecol 2013; 41: 102-113. DOI: 10.1002/uog.12342. Ultrasound Obstet. Gynecol.\u003c/li\u003e\n \u003cli\u003eHardarson T, Hanson C, Sj\u0026ouml;gren a, Lundin K (2001) Human embryos with unevenly sized blastomeres have lower pregnancy and implantation rates: indications for aneuploidy and multinucleation. Hum Reprod 16:313\u0026ndash;318. https://doi.org/10.1093/humrep/16.2.313\u003c/li\u003e\n \u003cli\u003eSullivan LM, Massaro JM, D\u0026rsquo;Agostino RB (2004) Presentation of multivariate data for clinical use: The Framingham Study risk score functions. Stat Med. https://doi.org/10.1002/sim.1742\u003c/li\u003e\n \u003cli\u003eBottomley C, Van Belle V, Pexsters A, et al (2011) A model and scoring system to predict outcome of intrauterine pregnancies of uncertain viability. Ultrasound Obstet Gynecol. https://doi.org/10.1002/uog.9007\u003c/li\u003e\n \u003cli\u003eGuha S, Van Belle V, Bottomley C, et al (2013) External validation of models and simple scoring systems to predict miscarriage in intrauterine pregnancies of uncertain viability. Hum Reprod. https://doi.org/10.1093/humrep/det342\u003c/li\u003e\n \u003cli\u003eLautmann K, Cordina M, Elson J, et al (2011) Clinical use of a model to predict the viability of early intrauterine pregnancies when no embryo is visible on ultrasound. Hum Reprod. https://doi.org/10.1093/humrep/der287\u003c/li\u003e\n \u003cli\u003eKhalil A, Syngelaki A, Maiz N, et al (2013) Maternal age and adverse pregnancy outcome: A cohort study. Ultrasound Obstet Gynecol. https://doi.org/10.1002/uog.12494\u003c/li\u003e\n \u003cli\u003ePillai RN, Konje JC, Tincello DG, Potdar N (2016) Role of serum biomarkers in the prediction of outcome in women with threatened miscarriage: A systematic review and diagnostic accuracy meta-analysis. Hum. Reprod. Update\u003c/li\u003e\n \u003cli\u003eKasius A, Smit JG, Torrance HL, et al (2014) Endometrial thickness and pregnancy rates after IVF: A systematic review and meta-analysis. Hum Reprod Update. https://doi.org/10.1093/humupd/dmu011\u003c/li\u003e\n \u003cli\u003eTuuli MG, Norman SM, Odibo AO, et al (2011) Perinatal outcomes in women with subchorionic hematoma: A systematic review and meta-analysis. Obstet. Gynecol.\u003c/li\u003e\n \u003cli\u003eBottomley C, Van Belle V, Kirk E, et al (2013) Accurate prediction of pregnancy viability by means of a simple scoring system. Hum Reprod. https://doi.org/10.1093/humrep/des352\u003c/li\u003e\n \u003cli\u003eAsato K, Mekaru K, Heshiki C, et al (2014) Subchorionic hematoma occurs more frequently in in vitro fertilization pregnancy. Eur J Obstet Gynecol Reprod Biol. https://doi.org/10.1016/j.ejogrb.2014.07.014\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable 1 \u0026nbsp;Comparisons of the parameters between 2 groups\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellpadding=\"0\" cellspacing=\"0\" width=\"811\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.838471023427868%\"\u003e\n \u003cp\u003e\u003cstrong\u003eParameter\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.166461159062885%\"\u003e\n \u003cp\u003e\u003cstrong\u003eOngoing pregnancy\u0026nbsp;\u003cbr\u003e\u0026nbsp;(12,051)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" width=\"19.852034525277436%\"\u003e\n \u003cp\u003e\u003cstrong\u003eEarly pregnancy loss\u0026nbsp;\u003cbr\u003e\u0026nbsp;(1,926)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.480887792848335%\"\u003e\n \u003cp\u003e\u003cstrong\u003eP\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.05672009864365%\"\u003e\n \u003cp\u003e\u003cstrong\u003eOR\u003c/strong\u003e\u003cstrong\u003e（\u003c/strong\u003e\u003cstrong\u003e95% CI\u003c/strong\u003e\u003cstrong\u003e）\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.605425400739826%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eMaternal age (years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e30.9\u0026plusmn;4.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e33.3\u0026plusmn;5.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.838471023427868%\"\u003e\n \u003cp\u003eBMI(kg/m2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.166461159062885%\"\u003e\n \u003cp\u003e21.8\u0026plusmn;2.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" width=\"19.852034525277436%\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;22.1\u0026plusmn;2.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.480887792848335%\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.05672009864365%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.605425400739826%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eInfertility duration (years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e4.0\u0026plusmn;3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e4.4\u0026plusmn;3.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eTransfer cycle\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e1.2\u0026plusmn;0.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e1.4\u0026plusmn;0.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eInfertility type\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003ePrimary\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e4673 (38.78%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e602 (31.26%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e1.393（1.257-1.544）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eSecondary\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e7378 (61.22%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e1324 (68.74%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eCause of infertility\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e831 (6.90%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e112 (5.82%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e0.014\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eFemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e6920 (57.42%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e1176 (61.06%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eCombined male and female\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e3764 (31.23%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e550 (28.56%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eUnexlained\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e536 (4.45%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e88 (4.57%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003e14-day HCG (mIU/ml)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e594.4\u0026plusmn;301.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e430.5\u0026plusmn;283.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eEM thickness on transfer\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e12.6\u0026plusmn;2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e12.3\u0026plusmn;1.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eInsemination methods\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eIVF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e5584 (46.34%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e829 (43.06%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eICSI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e2081 (17.27%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e293 (15.22%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eIVF/ICSI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e4386 (36.40%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e804 (41.72%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eNumber of embryos transferred\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e1.7\u0026plusmn;0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e1.7\u0026plusmn;0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e0.44NS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eIntrauterine hematomas\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003ePresence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e1928 (16.00%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e363 (18.85%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e0.820（0.724-0.928）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eAbsence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e10123 (84.00%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e1563 (81.15%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eGSD (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e18.5\u0026plusmn;3.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e13.2\u0026plusmn;4.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eYSD (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e3.6\u0026plusmn;0.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e2.6\u0026plusmn;1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.864197530864196%\"\u003e\n \u003cp\u003eCRL (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.185185185185185%\"\u003e\n \u003cp\u003e3.5\u0026plusmn;0.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"3.0864197530864197%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.666666666666668%\"\u003e\n \u003cp\u003e1.2\u0026plusmn;1.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.493827160493828%\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.074074074074074%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.62962962962963%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.838471023427868%\"\u003e\n \u003cp\u003eEHR (bpm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.166461159062885%\"\u003e\n \u003cp\u003e114.5\u0026plusmn;12.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" width=\"19.852034525277436%\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;42.4\u0026plusmn;53.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.480887792848335%\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.05672009864365%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.605425400739826%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"7\" width=\"100%\"\u003e\n \u003cp\u003eNote: NS =not significant.OR=odds ratio; CI = confidence interval;BMI = body mass index;HCG = human chorionic gonadotropin;\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eEM= endometrium; IVF = in vitro fertilization; ICSI = intracytoplasmic sperm injection;GSD = gestational sac diameter；\u003c/p\u003e\n \u003cp\u003eYSD = yolk sac diameter;CRL= crown-rump length; EHR = embryonic heart rate.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eTable 2 \u0026nbsp;Points associated with each of the categories of the risk factors\u003c/p\u003e\n\u003ctable border=\"1\" cellpadding=\"0\" cellspacing=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003eVariable\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.58578856152513%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003eReference value (W\u003csub\u003eij\u003c/sub\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026beta;\u003csub\u003ei\u003c/sub\u003e\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"21.317157712305026%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026Beta;\u003csub\u003ei\u0026nbsp;\u003c/sub\u003e\u003c/em\u003e(W\u003csub\u003eij\u003c/sub\u003e-W\u003csub\u003eiREF\u003c/sub\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.464471403812826%\"\u003e\n \u003cp\u003ePoints\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"18.02426343154246%\"\u003e\n \u003cp\u003eMA (years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"6.58578856152513%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"19.584055459272097%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"18.02426343154246%\"\u003e\n \u003cp\u003e0.0920\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e\u0026lt;29\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e26.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e-0.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e-2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e30-39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e34.50=W\u003csub\u003e1REF\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e\u0026ge;40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e42.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e0.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"18.02426343154246%\"\u003e\n \u003cp\u003eGSD (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.58578856152513%\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e-0.1150\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e\u0026lt;9.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e6.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e1.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e9.0-12.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e11.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e0.91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e13.0-27.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e19.00=W\u003csub\u003e2REF\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e\u0026gt;27.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e27.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e-0.95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e-2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"18.02426343154246%\"\u003e\n \u003cp\u003eCRL (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.58578856152513%\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e-0.2450\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e\u0026lt;2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e0.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e2.1-6.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e4.20=W\u003csub\u003e3REF\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e\u0026gt;6.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e6.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e-0.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e-1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"18.02426343154246%\"\u003e\n \u003cp\u003eEHR (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.58578856152513%\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e-0.0340\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e\u0026lt;100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e50.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e2.21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e100-130\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e115.00=W\u003csub\u003e4REF\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e\u0026ge;130\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e140.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e-0.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e-2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"18.02426343154246%\"\u003e\n \u003cp\u003eYSD (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.58578856152513%\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e-0.1590\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e\u0026lt;3.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e1.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e0.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e3.00~4.99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e4.00=W\u003csub\u003e5REF\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e\u0026ge;5.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.584055459272097%\"\u003e\n \u003cp\u003e6.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e0.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" width=\"18.02426343154246%\"\u003e\n \u003cp\u003eEM (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"6.58578856152513%\"\u003e\n \u003cp\u003e \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"19.584055459272097%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"18.02426343154246%\"\u003e\n \u003cp\u003e-0.074\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e\u0026lt;10.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"19.584055459272097%\"\u003e\n \u003cp\u003e5.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e0.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e10-14.99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"19.584055459272097%\"\u003e\n \u003cp\u003e12.50=W\u003csub\u003e6REF\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"bottom\" width=\"24.61005199306759%\"\u003e\n \u003cp\u003e\u0026ge;15.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"19.584055459272097%\"\u003e\n \u003cp\u003e16.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"18.02426343154246%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"21.317157712305026%\"\u003e\n \u003cp\u003e-0.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.464471403812826%\"\u003e\n \u003cp\u003e-1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003ePoints=\u0026beta;i (Wij-WiREF)/B \u0026nbsp; \u0026nbsp;B=5*0.0920\u003c/p\u003e\n\u003cp\u003eNote: MA = maternal age; GSD = gestational sac diameter；CRL= crown-rump length; EHR = embryonic heart rate;YSD = yolk sac diameter; EM = endometrium.\u003c/p\u003e\n\u003cp\u003eTable 3 \u0026nbsp;Scoring system derived from the binary LR model.\u003c/p\u003e\n\u003cdiv align=\"Left\"\u003e\n \u003ctable border=\"1\" cellpadding=\"0\" cellspacing=\"0\" width=\"584\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003eSum of points\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"20.71917808219178%\"\u003e\n \u003cp\u003eEstimated risk of miscarriage (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003eSensitivity (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003eSpecificity\u003c/p\u003e\n \u003cp\u003e(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003ePPV\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003eNPV\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003eACC\u003c/p\u003e\n \u003cp\u003e(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e-8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e0.18%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e100.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e0.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e13.30%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e13.30%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e-7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e0.24%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e100.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e0.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e13.30%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e13.30%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e-6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e0.31%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e100.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e0.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e13.30%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e13.30%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e-5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e0.54%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e100.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e0.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e13.30%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e13.30%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e-4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e0.81%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e100.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e0.11%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e13.32%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e100.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e13.40%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e-3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e1.24%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e99.69%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e0.79%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e13.36%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e94.34%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e13.95%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e-2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e1.85%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e99.28%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e5.32%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e13.86%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e97.95%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e17.82%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e-1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e2.84%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e93.89%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e34.88%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e18.12%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e97.38%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e42.74%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e4.20%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e91.72%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e46.37%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e20.79%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e97.33%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e52.40%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e7.33%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e80.23%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e83.80%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e43.18%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e96.51%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e83.32%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e11.02%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e75.98%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e91.74%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e58.53%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e96.14%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e89.64%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e15.57%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e70.91%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e96.22%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e74.21%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e95.57%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e92.85%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e22.03%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e68.01%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e97.55%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e81.01%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e95.21%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e93.62%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e30.03%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e62.84%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e98.79%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e88.87%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e94.54%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e94.01%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e39.55%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e66.87%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e98.11%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e84.44%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e95.07%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e93.95%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e50.59%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e57.04%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e99.02%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e89.89%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e93.76%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e93.43%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e60.50%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e49.48%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e99.41%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e92.82%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e92.77%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e92.77%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e70.67%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e39.13%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e99.57%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e93.33%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e91.42%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e91.53%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e78.54%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e26.71%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e99.83%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e95.91%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e89.87%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e90.10%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e84.90%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e15.63%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e99.92%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e96.79%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e88.53%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e88.71%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e89.51%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e6.11%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e99.95%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e95.16%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e87.40%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e87.47%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e92.65%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e3.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e100.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e100.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e87.04%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e87.10%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"10.95890410958904%\"\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"16.095890410958905%\"\u003e\n \u003cp\u003e95.42%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"19.17808219178082%\"\u003e\n \u003cp\u003e0.52%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e100.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.013698630136986%\"\u003e\n \u003cp\u003e100.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"14.554794520547945%\"\u003e\n \u003cp\u003e86.76%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" width=\"13.184931506849315%\"\u003e\n \u003cp\u003e86.76%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"10.95890410958904%\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd width=\"16.095890410958905%\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd width=\"4.623287671232877%\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd width=\"14.554794520547945%\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd width=\"13.013698630136986%\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd width=\"13.013698630136986%\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd width=\"14.554794520547945%\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd width=\"13.184931506849315%\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eNote: LR = logistic regression; PPV = positive predictive value;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eNPV= negative predictive value; ACC = accuracy.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 4 The classification of the results obtained using point 5 as the cutoff value\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"1\" cellpadding=\"0\" cellspacing=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"37.27810650887574%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" width=\"44.773175542406314%\"\u003e\n \u003cp\u003eScoring system\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"17.94871794871795%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"37.27810650887574%\"\u003e\n \u003cp\u003eTraining samples\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"14.990138067061144%\"\u003e\n \u003cp\u003eEPL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"29.783037475345168%\"\u003e\n \u003cp\u003eOngoing pregnancy\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"17.94871794871795%\"\u003e\n \u003cp\u003eTotal\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"37.27810650887574%\"\u003e\n \u003cp\u003eEPL(n)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"14.990138067061144%\"\u003e\n \u003cp\u003e607\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"29.783037475345168%\"\u003e\n \u003cp\u003e359\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"17.94871794871795%\"\u003e\n \u003cp\u003e966\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"37.27810650887574%\"\u003e\n \u003cp\u003eOngoing pregnancy\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"14.990138067061144%\"\u003e\n \u003cp\u003e76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"29.783037475345168%\"\u003e\n \u003cp\u003e6219\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"17.94871794871795%\"\u003e\n \u003cp\u003e6295\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"37.27810650887574%\"\u003e\n \u003cp\u003eEPL(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"14.990138067061144%\"\u003e\n \u003cp\u003e62.84%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"29.783037475345168%\"\u003e\n \u003cp\u003e37.16%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"17.94871794871795%\"\u003e\n \u003cp\u003e100.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"37.27810650887574%\"\u003e\n \u003cp\u003eOngoing pregnancy(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"14.990138067061144%\"\u003e\n \u003cp\u003e1.21%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"29.783037475345168%\"\u003e\n \u003cp\u003e98.79%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"17.94871794871795%\"\u003e\n \u003cp\u003e100.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"37.27810650887574%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eVerification sample\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"14.990138067061144%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"29.783037475345168%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"17.94871794871795%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"37.27810650887574%\"\u003e\n \u003cp\u003eEPL(n)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"14.990138067061144%\"\u003e\n \u003cp\u003e621\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"29.783037475345168%\"\u003e\n \u003cp\u003e339\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"17.94871794871795%\"\u003e\n \u003cp\u003e960\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"37.27810650887574%\"\u003e\n \u003cp\u003eOngoing pregnancy(n)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"14.990138067061144%\"\u003e\n \u003cp\u003e70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"29.783037475345168%\"\u003e\n \u003cp\u003e5686\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"17.94871794871795%\"\u003e\n \u003cp\u003e5756\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"37.27810650887574%\"\u003e\n \u003cp\u003eEPL(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"14.990138067061144%\"\u003e\n \u003cp\u003e64.69%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"29.783037475345168%\"\u003e\n \u003cp\u003e35.31%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"17.94871794871795%\"\u003e\n \u003cp\u003e100.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" width=\"37.27810650887574%\"\u003e\n \u003cp\u003eOngoing pregnancy(%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"14.990138067061144%\"\u003e\n \u003cp\u003e1.22%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"29.783037475345168%\"\u003e\n \u003cp\u003e98.78%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" width=\"17.94871794871795%\"\u003e\n \u003cp\u003e100.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eNote: EPL: early pregnancy loss\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"european-journal-of-medical-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ejmr","sideBox":"Learn more about [European Journal of Medical Research](http://eurjmedres.biomedcentral.com)","snPcode":"40001","submissionUrl":"https://submission.nature.com/new-submission/40001/3","title":"European Journal of Medical Research","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Miscarriage, early pregnancy loss, in vitro fertilization-embryo transfer, transvaginal sonography","lastPublishedDoi":"10.21203/rs.3.rs-2261371/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-2261371/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"In order to investigate a convenient simple scoring system for the prediction of early pregnancy loss (EPL) based on simple demographics, a retrospective study with 13,977 women undergoing transvaginal ultrasound scan on Days 27–29 after in vitro fertilization-embryo transfer (IVF-ET) from June 2016 and December 2017 was conducted. The first trimester pregnancy outcome was noted 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 point -8 to 14. Points 5 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, point 5 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 routinely collected data can be conveniently used for the prediction of EPL after ET.","manuscriptTitle":"A simple scoring system for the prediction of early pregnancy loss developed by following 13,977 infertile patients after in vitro fertilization","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2022-11-16 08:33:13","doi":"10.21203/rs.3.rs-2261371/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major revision","date":"2023-05-09T03:42:51+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2023-04-23T13:20:41+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"aca2c330-5ad9-4ad5-aa20-8e10445b9529","date":"2023-02-22T02:40:36+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"0b2344fa-cc7d-4468-b771-8cc89aec333d","date":"2023-02-21T07:56:13+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2023-02-18T05:20:04+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2023-02-16T10:48:09+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2022-11-14T07:41:19+00:00","index":"","fulltext":""},{"type":"submitted","content":"European Journal of Medical Research","date":"2022-11-11T03:18:53+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"european-journal-of-medical-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ejmr","sideBox":"Learn more about [European Journal of Medical Research](http://eurjmedres.biomedcentral.com)","snPcode":"40001","submissionUrl":"https://submission.nature.com/new-submission/40001/3","title":"European Journal of Medical Research","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"f8672d93-b9e9-41f1-b296-b0b6cca4b9fd","owner":[],"postedDate":"November 16th, 2022","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2023-08-18T04:12:05+00:00","versionOfRecord":{"articleIdentity":"rs-2261371","link":"https://doi.org/10.1186/s40001-023-01218-z","journal":{"identity":"european-journal-of-medical-research","isVorOnly":false,"title":"European Journal of Medical Research"},"publishedOn":"2023-07-14 01:08:02","publishedOnDateReadable":"July 14th, 2023"},"versionCreatedAt":"2022-11-16 08:33:13","video":"","vorDoi":"10.1186/s40001-023-01218-z","vorDoiUrl":"https://doi.org/10.1186/s40001-023-01218-z","workflowStages":[]},"version":"v1","identity":"rs-2261371","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-2261371","identity":"rs-2261371","version":["v1"]},"buildId":"oE6Zbj460LM0Up2FdVbMZ","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}