{"paper_id":"32ddde86-cb85-42dc-83c6-697bcd51c732","body_text":"The association between antithyroid antibodies in euthyroid women with recurrent pregnancy Loss Before and During Pregnancy | 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 Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article The association between antithyroid antibodies in euthyroid women with recurrent pregnancy Loss Before and During Pregnancy Yuyin Chen, Chao Yang, Xingming Zhong, Xinke Tang, Li Zhang, Jin Luo, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8640831/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: Antithyroid antibodies(ATAb),especially thyroid peroxidase antibodies (TPOAb), have been found to be related to recurrent pregnancy loss (RPL),but this relationship mainly focus on the patients before pregnancy. The aim of this study was to evaluate the association of ATAb with RPL before and during Pregnancy. Materials and Methods: The clinical data of women with RPL or with spontaneous pregnancy loss (SPL), who met inclusion criteria were registered from January 2017 to January 2024, were retrospectively analyzed. The presence of ATAb with times of SPL, the changes of ATAb before pregnancy and during in 19 to 28 weeks of gestation（19-28 WG） were noted. Results: In 19-28 WG, among the patients with 0, 1 and ≥2 times of SPL,and among TGAb positive patients with 0, 1 and ≥2 times of SPL, the TGAb concentrations were the highest in patients with ≥2 times of SPL ( P = 0.001 and 0.044), the TGAb concentrations in patients with 1 and ≥2 times of SPLwere significantly higher than that in patients with 0 time of SPL(P =0.0004 and 0.001; P =0.022 and 0.024). Before pregnancy, in patients with 1 and ≥2 times of SPL, the TGAb concentration were significantly lower(P =0.01 and 0.012), the TPOAb concentration were significantly higher(P =0.001 and 9.6E-7) than that in 19-28WG; in TGAb negative patients with 1 time of SPL,TGAb concentration were significantly lower(P =0.031) than that in 19-28WG;in ATAb , TGAb and TPOAb negative patients with ≥2 times of SPL,the concentration of TPOAb were significantly lower(P =0.002, 0.007 and 0.0004) than that in 19-28WG. Conclusions: In midtrimester of pregnancy,TGAb concentration increase,while TPOAb decrease, the association of TPOAb with SPL may become less obvious, but the association of TGAb with SPL may be much obvious, especially with ATAb, TGAb and TPOAb negative patients, TGAb may be a biomarker of pregnant women with history of RPL. Antithyroid antibodies Recurrent pregnancy Loss Pregnancy Introduction Recurrent pregnancy loss (RPL), is defined as consecutive loss of two or more pregnancies before the 20th week of gestation (1-2) . It is reported that RPL affects about 1-3% of women trying to conceive and results in physical and psychological distress, including bleeding, infection, pain, and surgical intervention (2) . The identified etiologies of RPL include increasing maternal age, maternal chromosomal and genetic abnormalities, uterine anatomic abnormalities, endocrine and metabolic disorders, prethrombotic state, sperm quality, lifestyle issues and auto-immunity (4-12) . A specific auto-immunity is defined as positivity of autoantibodies in blood sample without clinical or biological criteria for defined diseases. Thyroid autoimmunity (TA) is defined as the presence of antithyroid antibodies(ATAb), specifically thyroid globulin antibodies (TGAb) and thyroid peroxidase antibodies (TPOAb). The association of TA with miscarriage was first reported in 1990. Subsequently, TA has been found to be related to RPL irrespective of thyroid hormone status (13) , and TPOAb is related to early miscarriage rate in euthyroid women with RPL (14) . However, these studies mainly focus on the patients before pregnancy. In our research, the association of antithyroid antibodies (ATAb) including TGAb and TPOAb, with the times of spontaneous loss(SPL) before and during Pregnancy were investigated, in order to further evaluate the role of these antibodies in RPL. Materials and Methods Sample collection This was a retrospective study conducted and women with RPL were registered from January 2017 to January 2024 at the Reproductive Medicine Center, Department of Obstetrics and Gynecology, Affiliated Hospital of Guizhou Medical University, Guiyang, Chian. All the women in the study met the following Inclusion criteria: with a history of RPL, without reasons besides immunological abnormalities(URPL), and with normal serum levels of thyroid stimulating hormone (TSH), triiodothyronine(T3) and tetraiodothyronine (T4). Women with one time of spontaneous pregnancy loss(SPL) serve as control group two, while fertile woman with at least one living baby and without a history of previous spontaneous pregnancy loss, preterm deliveries, or still births serve as control group one. All the women in the study met the following exclusion criteria: uterine anomalies, parental chromosomal abnormalities, genital infection, endocrine disorders and male factor of the women’s partners and autoimmune disease. For URPL, aspirin and low-dose glucocorticoids were given for two weeks before preparation for pregnancy. aspirin was given 100mg/day and prednisone acetate was given 5mg/day. Once pregnancy was confirmed, aspirin and glucocorticoids were stopped and low molecular weight heparin was used according to D-dimer level during the course of pregnancy (15) . Before treatment at the time of non-menstruation, and in 19-28WG, the peripheral blood of the patients was collected before empty stomach and simultaneously tested for the presence of antithyroid antibodies(TGAb and TPOAb). The tests were performed in clinical laboratory of Affiliated Hospital of Guizhou Medical University. These tests were routine examination for patients with history of one or two spontaneous pregnancy loss and infertility, except that in control group one only been routinely tested for the presence ATAb during pregnancy. Chemiluminescence assay To detect TPOAb and TGAb, the automated electrochemi-luminescence immunoassay were performed on a Cobas e 602 platform (Roche Diagnostics, USA). The samples were checked according to the manufacturer's instruction. Briefly, mix 20 μL serum sample with Ru-labelled antibody against TPO or TG, add biotin-labelled TPO/TG and streptavidin coated particles to the mixture. The TPOAb/TGAb from sample and from Ru-labelled competitive bind with biotin-labelled TPO/TG to form antigen--antibody complexes. The complexes combine with the particles through the reaction between biotin and streptavidin. The combined particles were attached to electrode by magnetic attraction, and the electrochemiluminescence is triggered by the pressed electrode, while the uncombined particles were washed out. The concentration of serum sample to be tested was calculated according to the luminous intensity which is inversely proportional to concentration of sample to be tested. The normal value of antibodies against thyreoperoxidase (TPOAb) and thyroglobulin (TGAb) were equal or below 15 IU/mL and 28 IU/mL respectively, TGAb and TPOAb positive was defined as the value of the antibodies beyond normal range. Study was approved by the ethics committee of the Affifiliated Hospital of Guizhou Medical University, and all patients gave informed consent. Statistical analyses Statistical analyses were performed with the SPSS software package, version SPSS 26.0(SPSS, Chicago, USA). The 95% confidence intervals were used to measure the concentrations of TGAb and TPOAb. Student’s t-test was used for comparing two groups, while Kruskal-Wallis H test was used for comparison between multiple groups. We applied chi-square test to compare the difference among ratios. P < 0.05 was considered statistically significant. RESULTS 3.1 Comparing the presence of ATAb with times of spontaneous pregnancy loss before pregnancy To seek the relationship of positive rate and concentration of ATAb with times of SPL, the data from the patients whose sample have been tested for the presence of ATAs, was analyzed (Table 1). The results showed that before pregnancy, no significant differences of age were observed in patients with 1 and ≥2 times of spontaneous pregnancy losses (SPL), and in ATAb,TGAb, and TPOAb positive patients with 0, 1 and ≥2 times of SPL (Table 1, P >0.05). Before pregnancy, no significant differences of the concentration and positive rate of ATAb,TGAb, and TPOAb were observed between in patients with 1 and ≥2 times of SPL(Table 1). 3.2 Comparing the presence of ATAb with times of spontaneous pregnancy loss after pregnancy During in 19-28 WG, no significant differences of age were observed among the patients with 0, 1 and ≥2 times of SPL, and among the ATAb, TGAb, and TPOAb positive patients with 0, 1 and ≥2 times of SPL (Table 2, P >0.05), except between in patients with 1 and ≥2 times of SPL (Table 2, P =0.016). During in 19-28 WG, significant differences of TGAb concentration were observed among the patients with 0, 1 and ≥2 times of SPL, and among the TGAb positive patients with 0, 1 and ≥2 times of SPL. The 95% confidence interval (CI) of TGAb concentrations were 13.69(12.2,15.1), 18.01(13.19,60.36), 18.21(12.53,42.98) in the patients with 0, 1 and ≥2 times of SPL, and were 164.95(145.20,228.68), 351.45(253.15,554.88), 287.30(209.55,422.70) in TGAb patients with 0, 1 and ≥2 times of SPL respectively (P = 0.001 and 0.044 Kruskal-Wallis test, Table 2); significant differences of TGAb concentration were observed between in patients with 1 and 0 time of SPL (Student’s t-test, P = 0.0004), and between in patients with ≥2 and 0 time of SPL, (Student’s t-test, P = 0.001), and were observed between in TGAb positive patients with 1 and 0 time of SPL (Student’s t-test, P = 0.022), and between in patients with ≥2 and 0 time of SPL, (Student’s t-test, P = 0.024), except in patients with 2 and 1 time of SPL,and in TGAb positive patients with 2 and 1 time of SPL, no significant differences of TGAb concentration were observed between them. No significant differences of ATAb, TGAb, and TPOAb positive rate, and TPOAb concentration were observed among the patients with 0, 1 and ≥2 times of SPL.No significant differences of TGAb and TPOAb concentration were observed among the ATAb and TPOAb positive patients with 0, 1 and ≥2 times of SPL(Table 2). 3.3 The presence of ATAb before pregnancy and during in midtrimester of pregnancy in patients with SPL To seek the relationship of positive rate and concentration of ATAb before pregnancy and during pregnancy, the data from the patients with 1 and ≥2 times of SPL was analysed. The results showed that in patients with 1 and ≥2 times of SPL, no significant differences of age were observed between before and during pregnancy. In patients with 1 and 2 times of SPL, the concentration of TPOAb were significantly higher(Student’s t-test, P =0.001 and 9.6E-7, Table 3), but the concentration of TGAb were significantly lower(Student’s t-test, P =0.01 and 0.012, Table 3), than that during in midtrimester of pregnancy. In TGAb negative patients with 1 time of SPL, the concentration of TGAb were significantly lower than that during in midtrimester of pregnancy(Student’s t-test, P =0.031 Table 3), but no significant differences of TPOAb were observed between them. In ATAb,TGAb and TPOAb negative patients with 2 times of SPL, the concentration of TPOAb were significantly higher than that during in midtrimester of pregnancy(Student’s t-test, P =0.002, 0.007 and 0.000, Table 3), but no significant differences of TGAb concentration were observed between them. In ATAb, TGAb and TPOAb positive patients with 1 and ≥2 times of SPL, no significant differences of TGAb and TPOAb concentrations were observed between before and during pregnancy. In ATAb and and TPOAb negative patients with 1 time of SPL, no significant differences of TGAb and TPOAb concentrations were observed between before and during pregnancy(Table 3). The results suggest that from before pregnancy to during pregnancy, whether in patients with 1 or ≥2 times of SPL, the concentration TGAb was increased, mainly caused by the increase of TGAb in TGAb negative patients with 1 time of SPL, and TPOAb was decreased, mainly caused by the decrease of TPOAb in ATAb, TGAb and TPOAb negative patients with RPL From before pregnancy to during the midtrimester of pregnancy, in patients with 1 and 2 times of SPL, the ATAb positive rate is from 42.4% (25/59) to 27.8%(15/54), and from 39.% (48/123) to 30.8%(37/120), TGAb positive rate is from 33.9%(20/59) to 14.8%(8/54), and from 24.4% (30/123) to 17.5%(21/120), and the TPOAb positive rate is from 33.9% (20/59) to 25.9%(14/54), and from 31.7% (39/123) to 25.8%(31/120) (Table 1 and Table 2). The results suggest that whether in patients with 1 or ≥2 times of SPL, the positive of ATAb, TGAb and TPOAb were reduced after pregnancy. 3.4 Comparison of the clinical outcomes among RPL patients with ATAb, TGAb and TPOAb positive To check the early abortion rate and live birth rate in SPL patients with different kinds of antithyroid autoantibodies, the data from pregnant women with 1 and 2 times SPL was analyzed. The results showed that in pregnant women with SPL, no significant differences of age, early abortion rate and live birth rate were observed among patients who tested positive for TGAb and TPOAb, suggesting that TGAb and TPOAb may have similar effect on the pregnancy outcomes of SPL (Table 1). Discussion For the immunological cause of RPL, only antiphospholipid syndrom is recommended for screening by all guidelines, however, 50% of RPL cases remain unknown (16) and is necessary for further investigating. In this study, we analysed the relationship of ATAb with different times of SPL before and during pregnancy, and compared the clinical outcome among these patients, in order to explore the possible cause of the disease. For women having ATAb, they are less likely to hypothyroidism, the majority of them(96.3%) are euthyroid (17) . In this study, all the research object are euthyroid in order to exclude the influence of hypothyroidism. Although an obviously association of thyroid antibodies with sporadic abortion, has been proved, a 2-fold increase in the risk for pregnancy loss were observed in patients with positive for thyroid antibodies, it does not prove the causality of the antibodies with the disease (18) . The American Thyroid Association point that the association of thyroid antibodies with RPL are less robust (18) , but ESHER stated that a clear association is found between ATAb and RPL (17) . In the study, we explore the association of thyroid antibodies with RPL before and during midtrimester of pregnancy. It is reported that in RPL, no significant differences in the prevalence or titers of thyroid autoantibodies between in patients with two times of SPL and with three or more times of SPL (17) , our results e x hibited that both before and during midtrimester of pregnancy, the concentration and positive rate of ATAb,TGAb, and TPOAb were no significant differences between in patients with 1 and ≥2 times of SPL,further suggesting that ATAb may be associated with SPL, but may not be assosciated with the times of SPL. In women with RPL, Marai et al. reported that TPOAb are more relevant than TGAb, antiphospholipid antibodies (aPL) such as anti-cardiolipin (aCL), antiphosphatidyl-serine (aPS), antiprothrombin (aPT) and anti-beta 2 glycoprotein 1(aβ2GP1) (19) . In later report, the overwhelming majority of studies investigating thyroid autoimmunity and clinical outcomes used only TPOAb measurements and TPOAb are mostly studied, mainly concentrated in the association of the positive of this antibody with RPL (18,20) . In our study, before pregnancy,we did not investigate whether the concentration and positive rate of ATAb,TGAb, and TPOAb is associated with RPL, because of lacking control. During midtrimester of pregnancy, our data indicated that,whether the pregnant women is with one or with two times of SPL, a clear association is found between TGAb and SPL, especially in TGAb positive patients, but no obviously assosciation is found between TPOAb and SPL(Table 2). Further analysis of our data demonstrated that, during midtrimester of pregnancy, whether in patients with 1 or ≥2 times of SPL, although the TGAb positive rate was reduced, only a small portion of patients was positive for TGAb, the toatal TGAb concentration was increased, the gap of TGAb concentration is widening between in patients with 1 and 0 times of SPL, and between in patients with ≥2 and 0 times of SPL, these may explain why during midtrimester of pregnancy, the relationship of TGAb with SPL become more obvious. Our data suggests that TGAb is also associated with RPL. On the contrary, our data indicated that, during midtrimester of pregnancy, whether in patients with 1 or ≥2 times of SPL, not only the TPOAb positive rate was reduced, but also the toatal TPOAb concentration was decreased, the gap of TPOAb concentration is narrowing between in patients with 1 and 0 times of SPL, and between in patients with ≥2 and 0 times of SPL, these may explain why during midtrimester of pregnancy, the relationship of TPOAb with SPL become no obvious. The gap of TPOAb concentration become even more narrowing between in patients with ≥2 and 0 times of SPL, because both in patients with ≥2 times of SPL, and in ATAb,TGAb and TPOAb negative patients with ≥2 times of SPL, the TPOAb concentration was decreased sharply, the relationship of TPOAb with RPL become less obvious during midtrimester of pregnancy. In Marai’s study, TPOAb, TGAb, and aPL were determined by flowcytometric analysis, and the positive rate of TPOAb was 21% (8/38), the totally positive rate of autobodies(at least one of the TPOAb, TGAb and anti-ENA positive) was 31.6%(12/38), in RPL patients (19) . It is noted that the prevalence of TPOAb and TGAb was 6.3% and 7.6% in adult blood donors of Swedish Population (21) , in women of reproductive age, the prevalence of TPOAb is 8-14% (17) , and in women seeking fertility, the prevalence of isolated TPOAb and TGAb was 4% and 5% rescepctively (22) . In our data the TPOAb and TGAb were detected by chemiluminescence assay and the results showed that before pregnancy, the positive rate of TPOAb and TGAb was 31.7% (39/123) and 24.4% (30/123), that during the pregnancy, the positive rate of TPOAb and TGAb was 25.8%(31/120) and 17.5%(21/120), respectively in RPL patients, suggesting that the positive rate of TPOAb and TGAb is affected by the detecting method, state of pregnancy and perhaps by the sample size used for determining these antibodies. Anyway, the ESHRE guideline strong recommended screening of TSH and TPOAb in women with RPL (17) , our results suggest that TGAb may be screened in pregnant women with history of RPL. As we known, Th1 immunity is characterized by immune-inflammatory, Th2 immunity is characterized anti-inflammatory responses. During the peri-implantation period, Th1 immunity is dominant, which benefits for embryo implantation. After that, Th1 immunity is sift to Th2 immunity, and the predominant Th2 anti-inflammatory responses at the implantation site may induce maternal-fetal tolerance and protect the fetus from materal immune system. With the progress of pregnancy,after approximately 20 week of pregnancy, Th2 immunity is gradually sift to Th1 immunity, this re-shifting may be associated with the preparation for parturition.Under the dominance of Th2 immunity, excessive Th2 cells and Th2 cytokine are produce, the former may participate in autoantibody production, the later may induce autoreactive B cell activation, both enhance autoimmunity. After 20 week of pregnancy, Th1 immunity is gradually dominant,which may inhibite production of autoantibody (23,24) . Our data exhibits that whether the pregnant women is with one or with two times of SPL, the positive rate of ATAb, TGAb, TPOAb, and the concentration of TPOAb decrease, during in midtrimester of pregnancy compared with before pregnancy, these consistent with previous reports that ATAb(chiefly TPOAb) titers were highest in the first trimester, and decreased by about 60% over the course of gestation (18), suggesting that the reduction of Th2 immunity and increase of Th1 immunity during the midtrimester of pregnancy with the advancement of pregnancy may be partly responsible for these decrease. However, from before pregnancy to during the midtrimester of pregnancy, an investigate why the TGAb concentrations increase obviously in RPL patients should be carried out, in order to know more about the cause of RPL. For URPL with auto-immunity, anticoagulation and immunosuppression are recommended, the drug for the treatment include aspirin, glucocorticoids, and heparin (25-27) , In our method, we used aspirin and low dose glucocorticoids for two weeks before pregnancy. Once pregnancy was confirmed, aspirin and low dose glucocorticoids were stopped and low molecular weight heparin was used, to advoid the possible side effect of the drug on the fetus (28-29) . Our results showed that, for patients with a history of URPL and receiving treatment of anticoagulation and immunosuppression , the EABR and LBR are similar among thos e with ATAb, TGAb and TPOAb positive and ATAb negative. Since aspirin and low dose glucocorticoids are used for a short time before pregnancy, they are least likely affect the production of ATAb after 20 week of pregnancy. The mainly function of low molecular weight heparin is anticoagulation, Therefore, the medicine used in the study before and during pregnancy may have little effect on the concentration of ATAb, their change may be attributed by pregnancy with or without history of RPL. Conclusion In midtrimester of pregnancy, the positive rate of ATAb, TGAb, TPOAb and the concentration of TPOAb decrease in women with history of SPL, the concentration of TPOAb decrease obviously in patients with history of RPL, and in ATAb, TGAb and TPOAb negative patients with history of RPL, an association of TPOAb with SPL is no obvious, especially with ATAb, TGAb and TPOAb negative patients with history of RPL, the concentration of TGAb increase greatly in pregnant women with history of SPL. an association of TGAb with SPL is much obvious in pregnant women, and TGAb may be a biomarker of pregnant women with history of RPL. Abbreviations RPL Recurrent pregnancy loss ATAb Antithyroid antibodies TPOAb Thyroid peroxidase antibodies SPL Spontaneous pregnancy loss WG Weeks of gestation TGAb Thyroglobulin antibodies TA Thyroid autoimmunity URPL Unexplained recurrent pregnancy loss TSH Thyroid stimulating hormone T3 Triiodothyronine T4 Tetraiodothyronine CI Confidence interval EABR Early abortion rate LBR Live birth rate aPL Antiphospholipid antibodies aCL Anti-cardiolipin aPS Antiphosphatidyl-serine aPT Antiprothrombin aβ2GP1 Anti-beta 2 glycoprotein 1 Th1 T helper 1 cells Th2 T helper 2 cells Declarations Acknowledgements Not applicable. Funding This research was funded by the National Natural Science Foundation of China (http:// www.nsfc.gov.cn/ Grant No. 82260312) and Guizhou Provincial Health Commission Science and Technology Fund Project (Grant numbers: gzwkj2022-415), China. . Authors’ Contributions All authors read and ap proved the final manuscript. 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Thyroglobulin autoantibodies: is there any added value in the detection of thyroid autoimmunity in women consulting for fertility treatment?. Thyroid : official journal of the American Thyroid Association , 23 (8), 1022–1028. Wang, W., Sung, N., Gilman-Sachs, A., & Kwak-Kim, J. (2020). T Helper (Th) Cell Profiles in Pregnancy and Recurrent Pregnancy Losses: Th1/Th2/Th9/Th17/Th22/Tfh Cells. Frontiers in immunology , 11 , 2025. Tukaj, S., Bieber, K., Prüßmann, W., Prüßmann, J. N., Schmidt, E., Zillikens, D., Ludwig, R. J., & Kasperkiewicz, M. (2023). Bullous pemphigoid anti-BP180-NC16A autoantibody reactivity in healthy individuals is associated with marked hypovitaminosis D and Th2-like cytokine predominance. Archives of dermatological research , 315 (10), 2921–2926. Deng, T., Liao, X., & Zhu, S. (2022). Recent Advances in Treatment of Recurrent Spontaneous Abortion. Obstetrical & gynecological survey , 77 (6), 355–366. Cai, R., Yang, Q., Liao, Y., Qin, L., Han, J., & Gao, R. (2025). Immune Treatment Strategies in Unexplained Recurrent Pregnancy Loss. American journal of reproductive immunology (New York, N.Y. : 1989) , 93 (2), e70060. Song, Y., Wang, H. Y., Qiao, J., Liu, P., & Chi, H. B. (2017). Antiphospholipid Antibody Titers and Clinical Outcomes in Patients with Recurrent Miscarriage and Antiphospholipid Antibody Syndrome: A Prospective Study. Chinese medical journal , 130 (3), 267–272. Garza-Galvan, M. E., Ferrigno, A. S., Campos-Zamora, M., Bain, P. A., Easter, S. R., Kim, J., Figueras, F., Farber, M. K., & Lumbreras-Marquez, M. I. (2023). Low-dose aspirin use in the first trimester of pregnancy and odds of congenital anomalies: A meta-analysis of randomized controlled trials. International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics , 160 (2), 526–537. Peterson, E. A., Lynton, J., Bernard, A., Santillan, M. K., & Bettendorf, B. (2020). Rheumatologic Medication Use During Pregnancy. Obstetrics and gynecology , 135 (5), 1161–1176. Tables Tables are available in the Supplementary Files section. Additional Declarations No competing interests reported. Supplementary Files Tables.docx Cite Share Download PDF Status: Posted Version 1 posted 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board 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-8640831\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":true,\"archivedVersions\":[],\"articleType\":\"Research Article\",\"associatedPublications\":[],\"authors\":[{\"id\":583310960,\"identity\":\"e0f45c88-86b4-468e-9143-50e110945b1f\",\"order_by\":0,\"name\":\"Yuyin Chen\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Affiliated Hospital of Guizhou Medical University\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Yuyin\",\"middleName\":\"\",\"lastName\":\"Chen\",\"suffix\":\"\"},{\"id\":583310964,\"identity\":\"c2bcf159-f013-45bf-8e14-9046af9550d7\",\"order_by\":1,\"name\":\"Chao Yang\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Affiliated Hospital of Guizhou Medical University\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Chao\",\"middleName\":\"\",\"lastName\":\"Yang\",\"suffix\":\"\"},{\"id\":583310965,\"identity\":\"e2059f9b-cc7c-44a5-8e6f-0b69bf9ed4f4\",\"order_by\":2,\"name\":\"Xingming Zhong\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Guangdong Provincial People's Hospital\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Xingming\",\"middleName\":\"\",\"lastName\":\"Zhong\",\"suffix\":\"\"},{\"id\":583310971,\"identity\":\"7c40f53a-ed77-48d8-ba7e-645acecc9f17\",\"order_by\":3,\"name\":\"Xinke Tang\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Affiliated Hospital of Guizhou Medical University\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Xinke\",\"middleName\":\"\",\"lastName\":\"Tang\",\"suffix\":\"\"},{\"id\":583310977,\"identity\":\"4c39ad9e-94da-4c41-a2af-9476ba6276ad\",\"order_by\":4,\"name\":\"Li Zhang\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Affiliated Hospital of Guizhou Medical University\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Li\",\"middleName\":\"\",\"lastName\":\"Zhang\",\"suffix\":\"\"},{\"id\":583310980,\"identity\":\"f589ef7a-b68b-4a85-b442-105fa9597649\",\"order_by\":5,\"name\":\"Jin Luo\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Affiliated Hospital of Guizhou Medical University\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Jin\",\"middleName\":\"\",\"lastName\":\"Luo\",\"suffix\":\"\"},{\"id\":583310983,\"identity\":\"1d32549a-c7f7-40cf-9d6e-12cb2613373b\",\"order_by\":6,\"name\":\"Xingyin Chen\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Affiliated Hospital of Guizhou Medical University\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Xingyin\",\"middleName\":\"\",\"lastName\":\"Chen\",\"suffix\":\"\"},{\"id\":583310984,\"identity\":\"e1e16ebe-0edc-4222-9f02-f7eacedb33f6\",\"order_by\":7,\"name\":\"Xiaojuan Chen\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Affiliated Hospital of Guizhou Medical University\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Xiaojuan\",\"middleName\":\"\",\"lastName\":\"Chen\",\"suffix\":\"\"},{\"id\":583310985,\"identity\":\"cd142914-55ee-4af6-b075-ce5306dada13\",\"order_by\":8,\"name\":\"Shuyun Zhao\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Affiliated Hospital of Guizhou Medical University\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Shuyun\",\"middleName\":\"\",\"lastName\":\"Zhao\",\"suffix\":\"\"},{\"id\":583310988,\"identity\":\"c856a5b5-60c0-4f03-a078-54595f559901\",\"order_by\":9,\"name\":\"Guanyou Huang\",\"email\":\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA/0lEQVRIiWNgGAWjYBCDBDD5sQFEMjYeIFoL48wGBgkg1UC8FmZesBYGBrxa5COSnz3mqTicZ3D87OHXtjts6nTbDwNtqbGJxqXF8EaauTHPmcPFBmfy0qxzz6RJmJ1JBGo5lpbbgEvLjAQzad62w4kbDuSYGee2HZYwOwDUwthwGI+W9G8QLeffmBlbgrScf4hfi7xEDtSWGznGjxlBWm4QsMWA502Z5Jwz6Ykzb7wxY+xtS5PcdgNoSwIev8i3p2+TeFNhndh3Psf4w882G36z8+kPH3yoscFtywEGBiYeCJtNAi6cgEM52BagWYw/IGzmD3gUjoJRMApGwQgGAKxlZ6Z8HDEoAAAAAElFTkSuQmCC\",\"orcid\":\"\",\"institution\":\"Affiliated Hospital of Guizhou Medical University\",\"correspondingAuthor\":true,\"prefix\":\"\",\"firstName\":\"Guanyou\",\"middleName\":\"\",\"lastName\":\"Huang\",\"suffix\":\"\"}],\"badges\":[],\"createdAt\":\"2026-01-19 15:23:50\",\"currentVersionCode\":1,\"declarations\":\"\",\"doi\":\"10.21203/rs.3.rs-8640831/v1\",\"doiUrl\":\"https://doi.org/10.21203/rs.3.rs-8640831/v1\",\"draftVersion\":[],\"editorialEvents\":[],\"editorialNote\":\"\",\"failedWorkflow\":false,\"files\":[{\"id\":105800402,\"identity\":\"ef54b009-b446-45a3-9be4-c4f40d9cb6ff\",\"added_by\":\"auto\",\"created_at\":\"2026-03-31 09:28:09\",\"extension\":\"pdf\",\"order_by\":0,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"manuscript-pdf\",\"size\":718620,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"manuscript.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8640831/v1/a7f11648-6def-4570-84ac-106b2a2ead76.pdf\"},{\"id\":101667817,\"identity\":\"02dfa7a0-76a2-4983-a656-57c414209f33\",\"added_by\":\"auto\",\"created_at\":\"2026-02-02 11:59:58\",\"extension\":\"docx\",\"order_by\":1,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"supplement\",\"size\":25315,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"Tables.docx\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-8640831/v1/13c7974cf090f2a16367cd81.docx\"}],\"financialInterests\":\"No competing interests reported.\",\"formattedTitle\":\"The association between antithyroid antibodies in euthyroid women with recurrent pregnancy Loss Before and During Pregnancy\",\"fulltext\":[{\"header\":\"Introduction\",\"content\":\"\\u003cp\\u003eRecurrent pregnancy loss (RPL), is defined as consecutive loss of two or more pregnancies before the 20th week of gestation\\u003csup\\u003e(1-2)\\u003c/sup\\u003e. It is reported that RPL affects about 1-3% of women trying to conceive and results in physical and psychological distress, including bleeding, infection, pain, and surgical intervention\\u003csup\\u003e(2)\\u003c/sup\\u003e. The identified etiologies of RPL include increasing maternal age, maternal chromosomal and genetic abnormalities, uterine anatomic abnormalities, endocrine and metabolic disorders, prethrombotic state, sperm quality, lifestyle issues and auto-immunity\\u003csup\\u003e(4-12)\\u003c/sup\\u003e.\\u003c/p\\u003e\\n\\u003cp\\u003eA specific auto-immunity is defined as positivity of autoantibodies in blood sample without clinical or biological criteria for defined diseases. Thyroid autoimmunity (TA) is defined as the presence of antithyroid antibodies(ATAb), \\u0026nbsp;specifically thyroid globulin antibodies (TGAb) and thyroid peroxidase antibodies (TPOAb). The association of TA with miscarriage was first reported in 1990. Subsequently, TA has been found to be related to RPL irrespective of thyroid hormone status\\u003csup\\u003e(13)\\u003c/sup\\u003e, and TPOAb is related to early miscarriage rate in euthyroid women with RPL\\u003csup\\u003e(14)\\u003c/sup\\u003e. However, these studies mainly focus on the patients before pregnancy. In our research, the association of antithyroid antibodies (ATAb) including TGAb and TPOAb, with the times of spontaneous loss(SPL) before and during Pregnancy were investigated, in order to further evaluate the role of these antibodies in RPL.\\u003c/p\\u003e\"},{\"header\":\"Materials and Methods\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003e\\u003cem\\u003eSample collection\\u003c/em\\u003e\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThis was a retrospective study conducted and women with RPL were registered from January 2017 to January 2024 at the Reproductive Medicine Center, Department of Obstetrics and Gynecology, Affiliated Hospital of Guizhou Medical University, Guiyang, Chian. All the women in the study met the following Inclusion criteria: with a history of RPL, without reasons besides immunological abnormalities(URPL), and with normal serum levels of thyroid stimulating hormone (TSH), triiodothyronine(T3) and tetraiodothyronine (T4). Women with one time of spontaneous pregnancy loss(SPL) serve as control group two, while fertile woman with at least one living baby and without a history of previous spontaneous pregnancy loss, preterm deliveries, or still births serve as control group one. All the women in the study met the following exclusion criteria: uterine anomalies, parental chromosomal abnormalities, genital infection, endocrine disorders and male factor of the women\\u0026rsquo;s partners and autoimmune disease. \\u003c/p\\u003e\\n\\u003cp\\u003eFor URPL, aspirin and low-dose glucocorticoids were given for two weeks before preparation for pregnancy. aspirin was given 100mg/day and prednisone acetate was given 5mg/day. Once pregnancy was confirmed, aspirin and glucocorticoids were stopped and low molecular weight heparin was used according to D-dimer level during the course of pregnancy\\u003csup\\u003e (15)\\u003c/sup\\u003e.\\u003c/p\\u003e\\n\\u003cp\\u003eBefore treatment at the time of non-menstruation, and in 19-28WG, the peripheral blood of the patients was collected before empty stomach and simultaneously tested for the presence of antithyroid antibodies(TGAb and TPOAb). The tests were performed in clinical laboratory of Affiliated Hospital of Guizhou Medical University. These tests were routine examination for patients with history of one or two spontaneous pregnancy loss and infertility, except that in control group one only been routinely tested for the presence ATAb during pregnancy. \\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003e\\u003cem\\u003eChemiluminescence assay\\u003c/em\\u003e\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eTo detect TPOAb and TGAb, the automated electrochemi-luminescence immunoassay were performed on a Cobas e 602 platform (Roche Diagnostics, USA). The samples were checked according to the manufacturer\\u0026apos;s instruction. Briefly, mix 20 \\u0026mu;L serum sample with Ru-labelled antibody against TPO or TG, add biotin-labelled TPO/TG and streptavidin coated particles to the mixture. The TPOAb/TGAb from sample and from Ru-labelled competitive bind with biotin-labelled TPO/TG to form antigen--antibody complexes. The complexes combine with the particles through the reaction between biotin and streptavidin. The combined particles were attached to electrode by magnetic attraction, and the electrochemiluminescence is triggered by the pressed electrode, while the uncombined particles were washed out. The concentration of serum sample to be tested was calculated according to the luminous intensity which is inversely proportional to concentration of sample to be tested.\\u003c/p\\u003e\\n\\u003cp\\u003eThe normal value of antibodies against thyreoperoxidase (TPOAb) and thyroglobulin (TGAb) were equal or below 15 IU/mL and 28 IU/mL respectively, TGAb and TPOAb positive was defined as the value of the antibodies beyond normal range. Study was approved by the ethics committee of the Affifiliated Hospital of Guizhou Medical University, and all patients gave informed consent.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003e\\u003cem\\u003eStatistical analyses\\u003c/em\\u003e\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eStatistical analyses were performed with the SPSS software package, version SPSS 26.0(SPSS, Chicago, USA). The 95% confidence intervals were used to measure the concentrations of TGAb and TPOAb. Student\\u0026rsquo;s t-test was used for comparing two groups, while Kruskal-Wallis H test was used for comparison between multiple groups. We applied chi-square test to compare the difference among ratios. P \\u0026lt; 0.05 was considered statistically significant. \\u003c/p\\u003e\"},{\"header\":\"RESULTS\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003e\\u003cem\\u003e3.1 Comparing the presence of ATAb with times of spontaneous pregnancy loss before pregnancy\\u003c/em\\u003e\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003e\\u0026nbsp; \\u0026nbsp; \\u0026nbsp; \\u0026nbsp; \\u0026nbsp; \\u0026nbsp;\\u0026nbsp;To seek the relationship of positive rate and concentration of ATAb with times of SPL, the data from the patients whose sample have been tested for the presence of ATAs, was analyzed (Table 1). The results showed that before pregnancy, no significant differences of age were observed in patients with 1 and \\u0026ge;2 times of spontaneous pregnancy losses (SPL), and in ATAb,TGAb, and TPOAb positive patients with 0, 1 and \\u0026ge;2 times of SPL (Table 1, \\u003cem\\u003eP\\u003c/em\\u003e \\u0026gt;0.05). Before pregnancy, no significant differences of the concentration and positive rate of ATAb,TGAb, and TPOAb were observed between in patients with 1 and \\u0026ge;2 times of SPL(Table 1).\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003e\\u003cem\\u003e3.2 Comparing the presence of ATAb with times of spontaneous pregnancy loss after pregnancy\\u003c/em\\u003e\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eDuring in 19-28 WG, no significant differences of age were observed among the patients with 0, 1 and \\u0026ge;2 times of SPL, and among the ATAb, TGAb, and TPOAb positive patients with 0, 1 and \\u0026ge;2 times of SPL (Table 2, \\u003cem\\u003eP\\u003c/em\\u003e \\u0026gt;0.05), except between \\u0026nbsp;in patients with 1 and \\u0026ge;2 times of SPL (Table 2, \\u003cem\\u003eP\\u003c/em\\u003e =0.016). During in 19-28 WG, significant differences of TGAb concentration were observed among the patients with 0, 1 and \\u0026ge;2 times of SPL, and among the TGAb positive patients with 0, 1 and \\u0026ge;2 times of SPL. The 95% confidence interval (CI) of TGAb concentrations were 13.69(12.2,15.1), 18.01(13.19,60.36),\\u0026nbsp; \\u0026nbsp; \\u0026nbsp; \\u0026nbsp; \\u0026nbsp; \\u0026nbsp;\\u0026nbsp;18.21(12.53,42.98)\\u0026nbsp; \\u0026nbsp; \\u0026nbsp;in the patients with 0, 1 and \\u0026ge;2 times of SPL, and were 164.95(145.20,228.68), 351.45(253.15,554.88), 287.30(209.55,422.70) in TGAb patients with 0, 1 and \\u0026ge;2 times of SPL respectively (P = 0.001 and 0.044 Kruskal-Wallis test, Table 2); significant differences of TGAb concentration were observed between in patients with 1 and 0 time of SPL (Student\\u0026rsquo;s t-test, P = 0.0004), and between in patients with \\u0026ge;2 \\u0026nbsp;and 0 time of SPL, \\u0026nbsp;(Student\\u0026rsquo;s t-test, P = 0.001), and were observed between in TGAb positive patients with 1 and 0 time of SPL (Student\\u0026rsquo;s t-test, P = 0.022), and between in patients with \\u0026ge;2 and 0 time of SPL, (Student\\u0026rsquo;s t-test, P = 0.024), except in patients with 2 and 1 time of SPL,and \\u0026nbsp;in TGAb positive patients with 2 and 1 time of SPL, no significant differences of TGAb concentration were observed between them. No significant differences of \\u0026nbsp; ATAb, TGAb, and TPOAb positive rate, and TPOAb concentration were observed among the patients with 0, 1 and \\u0026ge;2 times of SPL.No significant differences of TGAb and TPOAb concentration were observed among the ATAb and TPOAb positive patients with 0, 1 and \\u0026ge;2 times of SPL(Table 2).\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003e\\u003cem\\u003e3.3 The presence of ATAb before pregnancy and during in midtrimester of pregnancy in patients with SPL\\u003c/em\\u003e\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eTo seek the relationship of positive rate and concentration of ATAb before pregnancy and during pregnancy, the data from the patients with 1 and \\u0026ge;2 times of SPL was analysed. The results showed that in patients with 1 and \\u0026ge;2 times of SPL, no significant differences of age were observed between before and during pregnancy. In patients with 1 and 2 times of SPL, the concentration of TPOAb were significantly higher(Student\\u0026rsquo;s t-test, P =0.001 and 9.6E-7, Table 3), but the concentration of TGAb were significantly lower(Student\\u0026rsquo;s t-test, P =0.01 and 0.012, Table 3), than that during in midtrimester of pregnancy. In TGAb negative patients with 1 time of SPL, the concentration of TGAb were significantly lower than that during in midtrimester of pregnancy(Student\\u0026rsquo;s t-test, P =0.031 Table 3), but no significant differences of TPOAb were observed between them. In ATAb,TGAb and TPOAb negative patients with 2 times of SPL, the concentration of TPOAb were significantly higher \\u0026nbsp;than that during in midtrimester of pregnancy(Student\\u0026rsquo;s t-test, P =0.002, 0.007 and 0.000, Table 3), but no significant differences of TGAb concentration were observed between them. In ATAb, TGAb and TPOAb positive patients with 1 and \\u0026ge;2 times of SPL, no significant differences of TGAb and TPOAb concentrations were observed between before and during pregnancy. In ATAb and and TPOAb negative patients with 1 time of SPL, no significant differences of TGAb and TPOAb concentrations were observed between before and during pregnancy(Table 3).\\u003c/p\\u003e\\n\\u003cp\\u003eThe results suggest that \\u0026nbsp;from before pregnancy to during pregnancy, whether in patients with 1 or \\u0026ge;2 times of SPL, the concentration TGAb was increased, mainly caused by the increase of TGAb in TGAb negative patients with 1 time of SPL, and TPOAb was decreased, mainly caused by the decrease of TPOAb in ATAb, TGAb and TPOAb negative patients with RPL\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u0026nbsp; From before pregnancy to during the midtrimester of pregnancy, in patients with 1 and 2 times of SPL, the ATAb positive rate is from 42.4% (25/59) to 27.8%(15/54), and from 39.% (48/123) to 30.8%(37/120), TGAb positive rate is from 33.9%(20/59) to 14.8%(8/54), and from 24.4% (30/123) to 17.5%(21/120), and the TPOAb positive rate is from 33.9% (20/59) to 25.9%(14/54), and from 31.7% (39/123) to 25.8%(31/120) (Table 1 and Table 2). The results suggest that whether in patients with 1 or \\u0026ge;2 times of SPL, the positive of ATAb, TGAb and TPOAb \\u0026nbsp;were \\u0026nbsp;reduced after pregnancy.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003e\\u003cem\\u003e\\u0026nbsp;3.4 Comparison of the clinical outcomes among RPL patients with ATAb, TGAb and TPOAb positive\\u003c/em\\u003e\\u003c/strong\\u003e\\u003cstrong\\u003e\\u0026nbsp;\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eTo check the early abortion rate and live birth rate in SPL patients with different kinds of antithyroid autoantibodies, the data from pregnant women with 1 and 2 times SPL was analyzed. The results showed that in pregnant women with SPL, no significant differences of age, early abortion rate and live birth rate were observed among patients who tested positive for TGAb and TPOAb, suggesting that TGAb and TPOAb may have similar effect on the pregnancy outcomes of SPL (Table 1).\\u0026nbsp;\\u003c/p\\u003e\"},{\"header\":\"Discussion\",\"content\":\"\\u003cp\\u003eFor the immunological cause of RPL, only antiphospholipid syndrom is recommended for screening by all guidelines, however, 50% of RPL cases remain unknown\\u003csup\\u003e(16)\\u003c/sup\\u003e and is necessary for further investigating. In this study, we analysed the relationship of ATAb with different times of SPL before and during pregnancy, and compared the clinical outcome among these patients, in order to explore the possible cause of the disease.\\u003c/p\\u003e\\n\\u003cp\\u003eFor women having ATAb, they are less likely to hypothyroidism, the majority of them(96.3%) are euthyroid\\u003csup\\u003e(17)\\u003c/sup\\u003e. In this study, all the research object are euthyroid in order to exclude the influence of hypothyroidism. Although an obviously association of thyroid antibodies with sporadic abortion, has been proved, a 2-fold increase in the risk for pregnancy loss were observed in patients with positive for thyroid antibodies, it does not prove the causality of the antibodies with the disease\\u003csup\\u003e(18)\\u003c/sup\\u003e. The American Thyroid Association point that the association of thyroid antibodies with RPL are less robust\\u003csup\\u003e(18)\\u003c/sup\\u003e, but ESHER stated that a clear association is found between ATAb and RPL\\u003csup\\u003e(17)\\u003c/sup\\u003e.\\u003c/p\\u003e\\n\\u003cp\\u003eIn the study, we explore the association of thyroid antibodies with RPL before and during midtrimester of pregnancy. It is reported that in RPL, no significant differences in the prevalence or titers of thyroid autoantibodies between in patients with two times of SPL and with three or more times of SPL\\u003csup\\u003e(17)\\u003c/sup\\u003e, our results e\\u003cu\\u003ex\\u003c/u\\u003ehibited that both before and during midtrimester of pregnancy, the concentration and positive rate of ATAb,TGAb, and TPOAb were no significant differences between in patients with 1 and \\u0026ge;2 times of SPL,further suggesting that ATAb may be associated with SPL, but may not be assosciated with the times of SPL. \\u003c/p\\u003e\\n\\u003cp\\u003eIn women with RPL, Marai et al. reported that TPOAb are more relevant than TGAb, antiphospholipid antibodies (aPL) such as anti-cardiolipin (aCL), antiphosphatidyl-serine (aPS), antiprothrombin (aPT) and anti-beta 2 glycoprotein 1(a\\u0026beta;2GP1)\\u003csup\\u003e(19)\\u003c/sup\\u003e. In later report, the overwhelming majority of studies investigating thyroid autoimmunity and clinical outcomes used only TPOAb measurements and TPOAb are mostly studied, mainly concentrated in the association of the positive of this antibody with RPL\\u003csup\\u003e(18,20)\\u003c/sup\\u003e. In our study, before pregnancy,we did not investigate whether the concentration and positive rate of ATAb,TGAb, and TPOAb is associated with RPL, because of lacking control. During midtrimester of pregnancy, our data indicated that,whether the pregnant women is with one or with two times of SPL, a clear association is found between TGAb and SPL, especially in TGAb positive patients, but no obviously assosciation is found between TPOAb and SPL(Table 2). Further analysis of our data demonstrated that, during midtrimester of pregnancy, whether in patients with 1 or \\u0026ge;2 times of SPL, although the TGAb positive rate was reduced, only a small portion of patients was positive for TGAb, the toatal TGAb concentration was increased, the gap of TGAb concentration is widening between in patients with 1 and 0 times of SPL, and between in patients with \\u0026ge;2 and 0 times of SPL, these may explain why during midtrimester of pregnancy, the relationship of TGAb with SPL become more obvious. Our data suggests that TGAb is also associated with RPL. On the contrary, our data indicated that, during midtrimester of pregnancy, whether in patients with 1 or \\u0026ge;2 times of SPL, not only the TPOAb positive rate was reduced, but also the toatal TPOAb concentration was decreased, the gap of TPOAb concentration is\\u0026ensp;narrowing between in patients with 1 and 0 times of SPL, and between in patients with \\u0026ge;2 and 0 times of SPL, these may explain why during midtrimester of pregnancy, the relationship of TPOAb with SPL become no obvious. The gap of TPOAb concentration \\u0026ensp;become even more narrowing between in patients with \\u0026ge;2 and 0 times of SPL, because both in patients with \\u0026ge;2 times of SPL, and in ATAb,TGAb and TPOAb negative patients with \\u0026ge;2 times of SPL, the TPOAb concentration was decreased sharply, the relationship of TPOAb with RPL become less obvious during midtrimester of pregnancy. \\u003c/p\\u003e\\n\\u003cp\\u003eIn Marai\\u0026rsquo;s study, TPOAb, TGAb, and aPL were determined by flowcytometric analysis, and the positive rate of TPOAb was 21% (8/38), the totally positive rate of autobodies(at least one of the TPOAb, TGAb and anti-ENA positive) was 31.6%(12/38), in RPL patients\\u003csup\\u003e(19)\\u003c/sup\\u003e. It is noted that the prevalence of TPOAb and TGAb was 6.3% and 7.6% in adult blood donors of Swedish Population\\u003csup\\u003e(21)\\u003c/sup\\u003e, in women of reproductive age, the prevalence of TPOAb is 8-14%\\u003csup\\u003e(17)\\u003c/sup\\u003e, and in women seeking fertility, the prevalence of isolated TPOAb and TGAb was 4% and 5% rescepctively\\u003csup\\u003e(22)\\u003c/sup\\u003e. In our data the TPOAb and TGAb were detected by chemiluminescence assay and the results showed that before pregnancy, the positive rate of TPOAb and TGAb was 31.7% (39/123) and 24.4% (30/123), that during the pregnancy, the positive rate of TPOAb and TGAb was 25.8%(31/120) and 17.5%(21/120), respectively in RPL patients, suggesting that the positive rate of TPOAb and TGAb is affected by the detecting method, state of pregnancy and perhaps by the sample size used for determining these antibodies. Anyway, the ESHRE guideline strong recommended screening of TSH and TPOAb in women with RPL\\u003csup\\u003e(17)\\u003c/sup\\u003e, our results suggest that TGAb may be screened in pregnant women with history of RPL. \\u003c/p\\u003e\\n\\u003cp\\u003eAs we known, Th1 immunity is characterized by immune-inflammatory, Th2 immunity is characterized anti-inflammatory responses. During the peri-implantation period, Th1 immunity is dominant, which benefits for embryo implantation. After that, Th1 immunity is sift to Th2 immunity, and the predominant Th2 anti-inflammatory responses at the implantation site may induce maternal-fetal tolerance and protect the fetus from materal immune system. With the progress of pregnancy,after approximately 20 week of pregnancy, Th2 immunity is gradually sift to Th1 immunity, this re-shifting may be associated with the preparation for parturition.Under the dominance of Th2 immunity, excessive Th2 cells and Th2 cytokine are produce, the former may participate in autoantibody production, the later may induce autoreactive B cell activation, both enhance autoimmunity. After 20 week of pregnancy, Th1 immunity is gradually dominant,which may inhibite production of autoantibody\\u003csup\\u003e(23,24)\\u003c/sup\\u003e. \\u003c/p\\u003e\\n\\u003cp\\u003eOur data exhibits that whether the pregnant women is with one or with two times of SPL, the positive rate of ATAb, TGAb, TPOAb, and the concentration of TPOAb decrease, during in midtrimester of pregnancy compared with before pregnancy, these consistent with previous reports that ATAb(chiefly TPOAb) titers were highest in the first trimester, and decreased by about 60% over the course of gestation (18), suggesting that the reduction of Th2 immunity and increase of Th1 immunity during the \\u003cem\\u003emidtrimester \\u003c/em\\u003eof pregnancy with the advancement of pregnancy may be partly responsible for these decrease. However, from before pregnancy to during the midtrimester of pregnancy, an investigate why the TGAb concentrations increase obviously in RPL patients should be carried out, in order to know more about the cause of RPL. \\u003c/p\\u003e\\n\\u003cp\\u003eFor URPL with auto-immunity, anticoagulation and immunosuppression are recommended, the drug for the treatment include aspirin, glucocorticoids, and heparin\\u003csup\\u003e(25-27)\\u003c/sup\\u003e, In our method, we used aspirin and low dose glucocorticoids for two weeks before pregnancy. Once pregnancy was confirmed, aspirin and low dose glucocorticoids were stopped and low molecular weight heparin was used, to advoid the possible side effect of the drug on the fetus\\u003csup\\u003e(28-29)\\u003c/sup\\u003e. Our results showed that, for patients with a history of URPL and receiving treatment of anticoagulation and immunosuppression , the EABR and LBR are similar among thos\\u003cu\\u003ee \\u003c/u\\u003ewith ATAb, TGAb and TPOAb positive and ATAb negative. Since aspirin and low dose glucocorticoids are used for a short time before pregnancy, they are least likely affect the production of ATAb after 20 week of pregnancy. The mainly function of low molecular weight heparin is anticoagulation, Therefore, the medicine used in the study before and during pregnancy may have little effect on the concentration of ATAb, their change may be attributed by pregnancy with or without history of RPL.\\u003c/p\\u003e\"},{\"header\":\"Conclusion\",\"content\":\"\\u003cp\\u003eIn midtrimester of pregnancy, the positive rate of ATAb, TGAb, TPOAb and the concentration of TPOAb decrease in women with history of SPL, the concentration of TPOAb decrease obviously in patients with history of RPL, and in ATAb, TGAb and TPOAb negative \\u0026nbsp;patients with history of RPL, an association of TPOAb with SPL is no obvious, especially with ATAb, TGAb and TPOAb negative patients with history of RPL, the concentration of TGAb increase greatly in pregnant women with history of SPL. an association of TGAb with SPL is much obvious in pregnant women, and TGAb may be a biomarker of pregnant women with history of RPL.\\u003c/p\\u003e\\n\"},{\"header\":\"Abbreviations\",\"content\":\"\\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eRPL\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eRecurrent pregnancy loss\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eATAb\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n \\u003c/table\\u003e\\n \\u003cp\\u003e\\u003cbr\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eAntithyroid antibodies\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eTPOAb\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n \\u003c/table\\u003e\\n \\u003cp\\u003e\\u003cbr\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eThyroid peroxidase antibodies\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eSPL\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eSpontaneous pregnancy loss\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eWG\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eWeeks of gestation\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eTGAb\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n \\u003c/table\\u003e\\n \\u003cp\\u003e\\u003cbr\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eThyroglobulin antibodies\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eTA\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n \\u003c/table\\u003e\\n \\u003cp\\u003e\\u003cbr\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eThyroid autoimmunity\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eURPL\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eUnexplained\\u0026nbsp;recurrent pregnancy loss\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eTSH\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eThyroid stimulating hormone\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eT3\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eTriiodothyronine\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eT4\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eTetraiodothyronine\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eCI\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eConfidence interval\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eEABR\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eEarly abortion rate\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eLBR\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n \\u003c/table\\u003e\\n \\u003cp\\u003e\\u003cbr\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eLive birth rate\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eaPL\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n \\u003c/table\\u003e\\n \\u003cp\\u003e\\u003cbr\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eAntiphospholipid antibodies\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eaCL\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n \\u003c/table\\u003e\\n \\u003cp\\u003e\\u003cbr\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eAnti-cardiolipin\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eaPS\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n \\u003c/table\\u003e\\n \\u003cp\\u003e\\u003cbr\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eAntiphosphatidyl-serine\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eaPT\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n \\u003c/table\\u003e\\n \\u003cp\\u003e\\u003cbr\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eAntiprothrombin\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003ea\\u0026beta;2GP1\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n \\u003c/table\\u003e\\n \\u003cp\\u003e\\u003cbr\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eAnti-beta 2 glycoprotein 1\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eTh1\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n \\u003c/table\\u003e\\n \\u003cp\\u003e\\u003cbr\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eT helper 1 cells\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 141px;\\\"\\u003e\\n \\u003ctable border=\\\"0\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eTh2\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n \\u003c/table\\u003e\\n \\u003cp\\u003e\\u003cbr\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 271px;\\\"\\u003e\\n \\u003cp\\u003eT helper 2 cells\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n\\u003c/table\\u003e\"},{\"header\":\"Declarations\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003eAcknowledgements\\u0026nbsp;\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eNot applicable.\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eFunding\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThis research was funded by the National Natural Science Foundation of China (http:// www.nsfc.gov.cn/ Grant No. 82260312) and Guizhou Provincial Health Commission Science and Technology Fund Project (Grant numbers: gzwkj2022-415), China. .\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAuthors\\u0026rsquo; Contributions\\u003c/strong\\u003e\\u003cstrong\\u003e\\u0026nbsp;\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eAll authors read and ap proved the final manuscript.\\u0026nbsp;X.Z., S.Z., G.H.;Conceptualization and , and Supervision. Y. C.,C.Y., X. T., L. Z., G.H.;Data collection, Methodology, Software analysis, Writing-reviewing and Editing the manuscript. Jin, Luo.,X,Chen., X, C.;Writing-original draft preparation, Visualization and Investigation.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eEthics Approval\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThis study was conducted in accordance with the Helsinki Declaration and was approved by the Ethics Committee of the Affiliated Hospital of Guizhou Medical University.\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eDisclosure statement\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eNo potential conflict of interest was reported by the author(s).\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eData availability statement\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eData are available from the corresponding author on reasonable request.\\u003c/p\\u003e\"},{\"header\":\"References\",\"content\":\"\\u003col\\u003e\\n\\u003cli\\u003ePractice Committee of the American Society for Reproductive Medicine (2013). 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M., Lewis, S., Middeldorp, S., Nelen, W., Peramo, B., Quenby, S., Vermeulen, N., \\u0026amp; Goddijn, M. (2018). ESHRE guideline: recurrent pregnancy loss. \\u003cem\\u003eHuman reproduction open\\u003c/em\\u003e, \\u003cem\\u003e2018\\u003c/em\\u003e(2), hoy004. \\u003c/li\\u003e\\n\\u003cli\\u003eYu, N., Kwak-Kim, J., \\u0026amp; Bao, S. (2023). Unexplained recurrent pregnancy loss: Novel causes and advanced treatment. \\u003cem\\u003eJournal of reproductive immunology\\u003c/em\\u003e, \\u003cem\\u003e155\\u003c/em\\u003e, 103785.\\u003c/li\\u003e\\n\\u003cli\\u003eVon Woon, E., Greer, O., Shah, N., Nikolaou, D., Johnson, M., \\u0026amp; Male, V. (2022). Number and function of uterine natural killer cells in recurrent miscarriage and implantation failure: a systematic review and meta-analysis. \\u003cem\\u003eHuman reproduction update\\u003c/em\\u003e, \\u003cem\\u003e28\\u003c/em\\u003e(4), 548\\u0026ndash;582. \\u003c/li\\u003e\\n\\u003cli\\u003eWu, Z., Wang, M., Liang, G., Jin, P., Wang, P., Xu, Y., Qian, Y., Jiang, X., Qian, J., \\u0026amp; Dong, M. (2021). Pro-Inflammatory Signature in Decidua of Recurrent Pregnancy Loss Regardless of Embryonic Chromosomal Abnormalities. \\u003cem\\u003eFrontiers in immunology\\u003c/em\\u003e, \\u003cem\\u003e12\\u003c/em\\u003e, 772729. \\u003c/li\\u003e\\n\\u003cli\\u003eHabets, D. H. J., Schl\\u0026uuml;tter, A., van Kuijk, S. M. J., Spaanderman, M. E. A., Al-Nasiry, S., \\u0026amp; Wieten, L. (2022). Natural killer cell profiles in recurrent pregnancy loss: Increased expression and positive associations with TACTILE and LILRB1. \\u003cem\\u003eAmerican journal of reproductive immunology (New York, N.Y. : 1989)\\u003c/em\\u003e, \\u003cem\\u003e88\\u003c/em\\u003e(5), e13612. \\u003c/li\\u003e\\n\\u003cli\\u003eFarshchi, M., Abdollahi, E., Saghafi, N., Hosseini, A., Fallahi, S., Rostami, S., Rostami, P., Rafatpanah, H., \\u0026amp; Habibagahi, M. (2022). Evaluation of Th17 and Treg cytokines in patients with unexplained recurrent pregnancy loss. \\u003cem\\u003eJournal of clinical and translational research\\u003c/em\\u003e, \\u003cem\\u003e8\\u003c/em\\u003e(3), 256\\u0026ndash;265.\\u003c/li\\u003e\\n\\u003cli\\u003eBagkou Dimakou, D., Tamblyn, J., Justin, C., Coomarasamy, A., \\u0026amp; Richter, A. (2022). Diagnosis and management of idiopathic recurrent pregnancy loss (RPL): Current immune testing and immunomodulatory treatment practice in the United Kingdom. \\u003cem\\u003eJournal of reproductive immunology\\u003c/em\\u003e, \\u003cem\\u003e153\\u003c/em\\u003e, 103662. \\u003c/li\\u003e\\n\\u003cli\\u003eChiokadze, M., B\\u0026auml;r, C., Pastuschek, J., Dons\\u0026apos;koi, B. V., Khazhylenko, K. G., Schleu\\u0026szlig;ner, E., Markert, U. R., \\u0026amp; Favaro, R. R. (2020). Beyond Uterine Natural Killer Cell Numbers in Unexplained Recurrent Pregnancy Loss: Combined Analysis of CD45, CD56, CD16, CD57, and CD138. \\u003cem\\u003eDiagnostics (Basel, Switzerland)\\u003c/em\\u003e, \\u003cem\\u003e10\\u003c/em\\u003e(9), 650. \\u003c/li\\u003e\\n\\u003cli\\u003eNielsen, J. R., Kolte, A. M., Bliddal, S., J\\u0026oslash;rgensen, H. L., Johnsen, M. G., Krog, M. C., Westergaard, D., \\u0026amp; Nielsen, H. S. (2024). Evaluating risk factors in recurrent pregnancy loss: A prospective cohort study and its impact on live birth outcomes. \\u003cem\\u003eJournal of reproductive immunology\\u003c/em\\u003e, \\u003cem\\u003e165\\u003c/em\\u003e, 104297. \\u003c/li\\u003e\\n\\u003cli\\u003eXie, J., Jiang, L., Sadhukhan, A., Yang, S., Yao, Q., Zhou, P., Rao, J., \\u0026amp; Jin, M. (2020). Effect of antithyroid antibodies on women with recurrent miscarriage: A meta-analysis. \\u003cem\\u003eAmerican journal of reproductive immunology (New York, N.Y. : 1989)\\u003c/em\\u003e, \\u003cem\\u003e83\\u003c/em\\u003e(6), e13238. \\u003c/li\\u003e\\n\\u003cli\\u003eLiu, M., Wang, D., Zhu, L., Yin, J., Ji, X., Zhong, Y., Gao, Y., Zhang, J., Liu, Y., Zhang, R., \\u0026amp; Chen, H. (2022). Association of thyroid peroxidase antibodies with the rate of first-trimester miscarriage in euthyroid women with unexplained recurrent spontaneous abortion. \\u003cem\\u003eFrontiers in endocrinology\\u003c/em\\u003e, \\u003cem\\u003e13\\u003c/em\\u003e, 966565. \\u003c/li\\u003e\\n\\u003cli\\u003eBai Xingli, Wang Jing, Zhao Shuyun, Wu Zirui, Chen Yuyin, Li Qinfen... \\u0026amp; Huang Guanyou. (2019). Analysis of the efficacy of low molecular weight heparin combined with Salvia miltiorrhiza in the treatment of recurrent miscarriage. Journal of Practical Obstetrics and Gynecology, 35(10), 774-779(Chinese).\\u003c/li\\u003e\\n\\u003cli\\u003eMumusoglu, S., Telek, S. B., \\u0026amp; Ata, B. (2025). Preimplantation genetic testing for aneuploidy in unexplained recurrent pregnancy loss: a systematic review and meta-analysis. \\u003cem\\u003eFertility and sterility\\u003c/em\\u003e, \\u003cem\\u003e123\\u003c/em\\u003e(1), 121\\u0026ndash;136. \\u003c/li\\u003e\\n\\u003cli\\u003eESHRE Guideline Group on RPL, Bender Atik, R., Christiansen, O. B., Elson, J., Kolte, A. M., Lewis, S., Middeldorp, S., Mcheik, S., Peramo, B., Quenby, S., Nielsen, H. S., van der Hoorn, M. L., Vermeulen, N., \\u0026amp; Goddijn, M. (2023). ESHRE guideline: recurrent pregnancy loss: an update in 2022. \\u003cem\\u003eHuman reproduction open\\u003c/em\\u003e, \\u003cem\\u003e2023\\u003c/em\\u003e(1), hoad002. \\u003c/li\\u003e\\n\\u003cli\\u003eAlexander, E. K., Pearce, E. N., Brent, G. A., Brown, R. S., Chen, H., Dosiou, C., Grobman, W. A., Laurberg, P., Lazarus, J. H., Mandel, S. J., Peeters, R. P., \\u0026amp; Sullivan, S. (2017). 2017 Guidelines of the American Thyroid Association for the Diagnosis and Management of Thyroid Disease During Pregnancy and the Postpartum. \\u003cem\\u003eThyroid : official journal of the American Thyroid Association\\u003c/em\\u003e, \\u003cem\\u003e27\\u003c/em\\u003e(3), 315\\u0026ndash;389. \\u003c/li\\u003e\\n\\u003cli\\u003eMarai, I., Carp, H., Shai, S., Shabo, R., Fishman, G., \\u0026amp; Shoenfeld, Y. (2004). Autoantibody panel screening in recurrent miscarriages. \\u003cem\\u003eAmerican journal of reproductive immunology (New York, N.Y. : 1989)\\u003c/em\\u003e, \\u003cem\\u003e51\\u003c/em\\u003e(3), 235\\u0026ndash;240. \\u003c/li\\u003e\\n\\u003cli\\u003eGodines-Enriquez, M. S., Miranda-Vel\\u0026aacute;squez, S., Enr\\u0026iacute;quez-P\\u0026eacute;rez, M. M., Arce-S\\u0026aacute;nchez, L., Mart\\u0026iacute;nez-Cruz, N., Flores-Robles, C. M., Aguayo-Gonz\\u0026aacute;lez, P., Morales-Hern\\u0026aacute;ndez, F. V., Villarreal-Barranca, A., Su\\u0026aacute;rez-Rico, B. V., Montoya-Estrada, A., Romo-Y\\u0026aacute;\\u0026ntilde;ez, J., \\u0026amp; Reyes-Mu\\u0026ntilde;oz, E. (2021). Prevalence of Thyroid Autoimmunity in Women with Recurrent Pregnancy Loss. \\u003cem\\u003eMedicina (Kaunas, Lithuania)\\u003c/em\\u003e, \\u003cem\\u003e57\\u003c/em\\u003e(2), 96. \\u003c/li\\u003e\\n\\u003cli\\u003eBergemann, N., Jonsdottir, B., Nilsson, A. L., Lantz, M., \\u0026amp; Lind, A. (2023). Prevalence of Thyroid Peroxidase and Thyroglobulin Autoantibodies in the Swedish Population. \\u003cem\\u003eExperimental and clinical endocrinology \\u0026amp; diabetes : official journal, German Society of Endocrinology [and] German Diabetes Association\\u003c/em\\u003e, \\u003cem\\u003e131\\u003c/em\\u003e(9), 456\\u0026ndash;462. \\u003c/li\\u003e\\n\\u003cli\\u003eUnuane, D., Velkeniers, B., Anckaert, E., Schiettecatte, J., Tournaye, H., Haentjens, P., \\u0026amp; Poppe, K. (2013). Thyroglobulin autoantibodies: is there any added value in the detection of thyroid autoimmunity in women consulting for fertility treatment?. \\u003cem\\u003eThyroid : official journal of the American Thyroid Association\\u003c/em\\u003e, \\u003cem\\u003e23\\u003c/em\\u003e(8), 1022\\u0026ndash;1028. \\u003c/li\\u003e\\n\\u003cli\\u003eWang, W., Sung, N., Gilman-Sachs, A., \\u0026amp; Kwak-Kim, J. (2020). T Helper (Th) Cell Profiles in Pregnancy and Recurrent Pregnancy Losses: Th1/Th2/Th9/Th17/Th22/Tfh Cells. \\u003cem\\u003eFrontiers in immunology\\u003c/em\\u003e, \\u003cem\\u003e11\\u003c/em\\u003e, 2025. \\u003c/li\\u003e\\n\\u003cli\\u003eTukaj, S., Bieber, K., Pr\\u0026uuml;\\u0026szlig;mann, W., Pr\\u0026uuml;\\u0026szlig;mann, J. N., Schmidt, E., Zillikens, D., Ludwig, R. J., \\u0026amp; Kasperkiewicz, M. (2023). Bullous pemphigoid anti-BP180-NC16A autoantibody reactivity in healthy individuals is associated with marked hypovitaminosis D and Th2-like cytokine predominance. \\u003cem\\u003eArchives of dermatological research\\u003c/em\\u003e, \\u003cem\\u003e315\\u003c/em\\u003e(10), 2921\\u0026ndash;2926. \\u003c/li\\u003e\\n\\u003cli\\u003eDeng, T., Liao, X., \\u0026amp; Zhu, S. (2022). Recent Advances in Treatment of Recurrent Spontaneous Abortion. \\u003cem\\u003eObstetrical \\u0026amp; gynecological survey\\u003c/em\\u003e, \\u003cem\\u003e77\\u003c/em\\u003e(6), 355\\u0026ndash;366. \\u003c/li\\u003e\\n\\u003cli\\u003eCai, R., Yang, Q., Liao, Y., Qin, L., Han, J., \\u0026amp; Gao, R. (2025). Immune Treatment Strategies in Unexplained Recurrent Pregnancy Loss. \\u003cem\\u003eAmerican journal of reproductive immunology (New York, N.Y. : 1989)\\u003c/em\\u003e, \\u003cem\\u003e93\\u003c/em\\u003e(2), e70060. \\u003c/li\\u003e\\n\\u003cli\\u003eSong, Y., Wang, H. Y., Qiao, J., Liu, P., \\u0026amp; Chi, H. B. (2017). Antiphospholipid Antibody Titers and Clinical Outcomes in Patients with Recurrent Miscarriage and Antiphospholipid Antibody Syndrome: A Prospective Study. \\u003cem\\u003eChinese medical journal\\u003c/em\\u003e, \\u003cem\\u003e130\\u003c/em\\u003e(3), 267\\u0026ndash;272. \\u003c/li\\u003e\\n\\u003cli\\u003eGarza-Galvan, M. E., Ferrigno, A. S., Campos-Zamora, M., Bain, P. A., Easter, S. R., Kim, J., Figueras, F., Farber, M. K., \\u0026amp; Lumbreras-Marquez, M. I. (2023). Low-dose aspirin use in the first trimester of pregnancy and odds of congenital anomalies: A meta-analysis of randomized controlled trials. \\u003cem\\u003eInternational journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics\\u003c/em\\u003e, \\u003cem\\u003e160\\u003c/em\\u003e(2), 526\\u0026ndash;537. \\u003c/li\\u003e\\n\\u003cli\\u003ePeterson, E. A., Lynton, J., Bernard, A., Santillan, M. K., \\u0026amp; Bettendorf, B. (2020). Rheumatologic Medication Use During Pregnancy. \\u003cem\\u003eObstetrics and gynecology\\u003c/em\\u003e, \\u003cem\\u003e135\\u003c/em\\u003e(5), 1161\\u0026ndash;1176. \\u003c/li\\u003e\\n\\u003c/ol\\u003e\"},{\"header\":\"Tables\",\"content\":\" \\u003cp\\u003eTables are available in the Supplementary Files section.\\u003c/p\\u003e\"}],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":true,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":false,\"hideJournal\":true,\"highlight\":\"\",\"institution\":\"\",\"isAcceptedByJournal\":false,\"isAuthorSuppliedPdf\":false,\"isDeskRejected\":\"\",\"isHiddenFromSearch\":false,\"isInQc\":false,\"isInWorkflow\":false,\"isPdf\":false,\"isPdfUpToDate\":true,\"isWithdrawnOrRetracted\":false,\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"researchsquare\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":true,\"externalIdentity\":\"\",\"sideBox\":\"\",\"snPcode\":\"\",\"submissionUrl\":\"/submission\",\"title\":\"Research Square\",\"twitterHandle\":\"researchsquare\",\"acdcEnabled\":true,\"dfaEnabled\":false,\"editorialSystem\":\"\",\"reportingPortfolio\":\"\",\"inReviewEnabled\":false,\"inReviewRevisionsEnabled\":true},\"keywords\":\"Antithyroid antibodies, Recurrent pregnancy Loss, Pregnancy \",\"lastPublishedDoi\":\"10.21203/rs.3.rs-8640831/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-8640831/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"\\u003cp\\u003e\\u003cstrong\\u003eBackground:\\u003c/strong\\u003e Antithyroid antibodies(ATAb),especially thyroid peroxidase antibodies (TPOAb), have been found to be related to recurrent pregnancy loss (RPL),but this relationship \\u0026nbsp;mainly focus on the patients before pregnancy. The aim of this study was to evaluate \\u0026nbsp;the association of ATAb with RPL before and during Pregnancy.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eMaterials and Methods: \\u003c/strong\\u003eThe clinical data of women with RPL or with spontaneous pregnancy loss (SPL), who met inclusion criteria were registered from January 2017 to January 2024, were retrospectively analyzed. The presence of ATAb with times of SPL, the changes of ATAb before pregnancy and during in 19 to 28 weeks of gestation（19-28 WG） were noted.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eResults:\\u003c/strong\\u003e In 19-28 WG, among the patients with 0, 1 and ≥2 times of SPL,and among TGAb positive patients with 0, 1 and ≥2 times of SPL, the TGAb concentrations were the highest in patients with ≥2 times of SPL (\\u003cem\\u003eP\\u003c/em\\u003e= 0.001 and 0.044), the TGAb concentrations in patients with 1 and ≥2 times of SPLwere significantly higher than that in patients with 0 time of SPL(P =0.0004 and 0.001; P =0.022 and 0.024). \\u0026nbsp;Before pregnancy, in patients with 1 and ≥2 times of SPL, the TGAb concentration were significantly lower(P =0.01 and 0.012), the TPOAb concentration were significantly higher(P =0.001 and 9.6E-7) than that in 19-28WG; in TGAb negative patients with 1 time of SPL,TGAb concentration were significantly lower(P =0.031) than that in 19-28WG;in ATAb , TGAb and TPOAb negative patients with ≥2 times of SPL,the concentration of TPOAb were significantly lower(P =0.002, 0.007 and 0.0004) than that \\u0026nbsp;in 19-28WG.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eConclusions:\\u003c/strong\\u003e In midtrimester of pregnancy,TGAb concentration increase,while \\u0026nbsp;TPOAb decrease, the association of TPOAb with SPL may become less obvious, but the association of TGAb with SPL may be much obvious, especially with ATAb, TGAb and TPOAb negative patients, TGAb may be a biomarker of pregnant women with history of RPL.\\u003c/p\\u003e\",\"manuscriptTitle\":\"The association between antithyroid antibodies in euthyroid women with recurrent pregnancy Loss Before and During Pregnancy\",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2026-02-02 11:59:39\",\"doi\":\"10.21203/rs.3.rs-8640831/v1\",\"editorialEvents\":[{\"type\":\"communityComments\",\"content\":0}],\"status\":\"published\",\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"researchsquare\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":true,\"externalIdentity\":\"\",\"sideBox\":\"\",\"snPcode\":\"\",\"submissionUrl\":\"/submission\",\"title\":\"Research Square\",\"twitterHandle\":\"researchsquare\",\"acdcEnabled\":true,\"dfaEnabled\":false,\"editorialSystem\":\"\",\"reportingPortfolio\":\"\",\"inReviewEnabled\":false,\"inReviewRevisionsEnabled\":true}}],\"origin\":\"\",\"ownerIdentity\":\"d2a34a9e-d632-402d-98c9-f20a6bbaa40d\",\"owner\":[],\"postedDate\":\"February 2nd, 2026\",\"published\":true,\"recentEditorialEvents\":[],\"rejectedJournal\":[],\"revision\":\"\",\"amendment\":\"\",\"status\":\"posted\",\"subjectAreas\":[],\"tags\":[],\"updatedAt\":\"2026-03-31T09:25:25+00:00\",\"versionOfRecord\":[],\"versionCreatedAt\":\"2026-02-02 11:59:39\",\"video\":\"\",\"vorDoi\":\"\",\"vorDoiUrl\":\"\",\"workflowStages\":[]},\"version\":\"v1\",\"identity\":\"rs-8640831\",\"journalConfig\":\"researchsquare\"},\"__N_SSP\":true},\"page\":\"/article/[identity]/[[...version]]\",\"query\":{\"redirect\":\"/article/rs-8640831\",\"identity\":\"rs-8640831\",\"version\":[\"v1\"]},\"buildId\":\"XKTyCvWXoU3ODBz1xrDgd\",\"isFallback\":false,\"isExperimentalCompile\":false,\"dynamicIds\":[84888],\"gssp\":true,\"scriptLoader\":[]}","source_license":"CC-BY-4.0","license_restricted":false}