EMAS position statement: Thyroid disease and menopause

INTRODUCTION

Thyroid diseases are common in women in their late reproductive years; therefore, thyroid disease and menopause may co-exist. Both conditions may present with a wide range of symptoms, leading to diagnostic challenges and delayed diagnosis. Aim To construct the first European Menopause and Andropause Society (EMAS) statement on thyroid diseases and menopause.

MATERIALS AND METHODS

Literature review and consensus of expert opinion (EMAS executive board members/experts on menopause and thyroid disease).

SUMMARY RECOMMENDATIONS

This position paper highlights the diagnostic and therapeutic dilemmas in managing women with thyroid disease during the menopausal transition, aiming to increase healthcare professionals' awareness of thyroid disorders and menopause-related symptoms. Clinical decisions regarding the treatment of both conditions should be made with caution and attention to the specific characteristics of this age group while adopting a personalized patient approach. The latter must include the family history, involvement of the woman in the decision-making, and respect for her preferences, to achieve overall well-being.

Autoimmune thyroid disease and ovarian hypofunction: a review of literature

Thyroid hormones(THs) are essential for the proper functioning of the ovaries, and multiple studies have shown that thyroid abnormalities, especially during adolescence and reproductive age, can lead to lifelong ovarian dysfunction. Autoimmune thyroid disease (AITD), one of the most common organ specific autoimmune diseases, is mainly mediated by cellular autoimmune reactions, and has strong inflammatory infiltration and immune active cells, including chemokines and cytokines, which are important components of ovarian aging. This suggests that autoimmune and inflammatory molecular processes may play a role in the emergence of ovarian dysfunction. The purpose of this review is to summarize recent in vivo and in vitro evidence of a complex relationship between AITD and ovarian dysfunction. AITD is closely related to the decline of ovarian function from the perspective of antibody, cytokine, oxidative stress, and genetic factors. Finally, some of the currently known treatments for AITD and hypo ovarian disease are summarized.

The association of thyroid autoimmunity with ovarian reserve in women with type 1 diabetes with and without polycystic ovary syndrome

The aim of the study was to investigate the relation between thyroid autoimmunity (TAI), reflected as the presence of thyroid peroxidase antibodies (TPOAb), and parameters of ovarian reserve in women with type 1 diabetes (T1DM) and polycystic ovary syndrome (PCOS). We studied 83 euthyroid women with T1DM (age - 26 ± 5 years, BMI - 24 ± 3 kg/m2) - 12 with PCOS and positive TPOAb (PCOS + TPOAb), 29 with PCOS with negative TPOAb (PCOS + noTPOAb), 18 without PCOS with positive TPOAb (noPCOS + TPOAb), 24 without PCOS with negative TPOAb (noPCOS + noTPOAb). Serum concentrations of anti-Müllerian hormone (AMH), sex hormones, TSH, thyroid hormones and TPOAb were assessed. The prevalence of TAI was comparable between PCOS and noPCOS. We did not observe differences in hormonal profile or AMH concentration between two PCOS groups-PCOS + TPOAb and PCOS + noTPOAb (p > 0.05). Women with PCOS + TPOAb had lower FSH concentration and higher LH/FSH index than noPCOS + noTPOAb (p = 0.027; p = 0.019, respectively). Moreover, PCOS + TPOAb had lower oestradiol level than noPCOS + TPOAb (p = 0.041). AMH concentration was higher in both groups with PCOS, independent of TPOAb presence, than in noPCOS + noTPOAb (both p < 0.001). The presence of positive TPOAb titre was not related to the studied parameters of ovarian reserve - AMH and ovarian follicle number. In multiple linear regression analysis, the only significant predictor of AMH in the whole studied group with T1DM was total daily insulin dose U/kg (β = - 0.264; p = 0.022). The presence of TAI did not affect the hormonal profile or ovarian reserve in women with T1DM with and without PCOS.

Intracytoplasmic Sperm Injection Versus In vitro Fertilization in Infertile Women with Thyroid Autoimmunity

Background: It has been reported that intracytoplasmic sperm injection (ICSI) may be the preferred fertilization method for women with thyroid autoimmunity (TAI) seeking assisted reproduction. We compared the reproductive outcomes of women with TAI who were treated with ICSI compared with in vitro fertilization (IVF). Methods: In this retrospective cohort study, we included women with infertility who were referred to the Reproductive Centre of Peking University Third Hospital for their first IVF/ICSI and embryo transfer (ET) treatment cycle from January 2019 to February 2021. In total, 2171 and 743 women with TAI underwent IVF and ICSI, respectively, while 8702 and 2668 women without TAI underwent IVF and ICSI, respectively. We examined the cumulative live birth rate (primary outcome) from the initiated stimulative cycle as well as the secondary outcomes of fertilization rate, rates of clinical pregnancy, and live birth after the first ET cycle. We compared the reproductive outcomes of women treated with IVF and ICSI according to TAI status. Multivariable logistic regression analyses were performed to adjust for relevant confounders. Results: Women who underwent ICSI had significantly higher fertilization rates than those who underwent IVF (median [interquartile range]: 0.6 [0.5-0.8] in the TAI-positive and IVF group vs. 0.7 [0.5-0.8] in the TAI-positive and ICSI group vs. 0.6 [0.5-0.8] the TAI-negative and IVF group vs. 0.7 [0.5-0.8] in the TAI-negative and ICSI group, p < 0.001). However, the rates of cumulative live births, clinical pregnancies, and live births were significantly lower among women with TAI who underwent ICSI than those who underwent IVF (cumulative live birth: 51.8% vs. 47%, adjusted odds ratio [aOR]: 0.80 [confidence interval, CI: 0.67-0.97]; clinical pregnancy: 43.0% vs. 38.8%, aOR: 0.81 [CI: 0.67-0.97]; live birth: 36.2% vs. 32.4%, aOR: 0.81 [CI: 0.66-0.98]). Conclusion: We observed that the use of ICSI in women with TAI was not associated with better assisted reproductive outcomes compared with IVF. Further prospective clinical trials are needed to confirm our findings.

The impact of thyroid autoimmunity on pregnancy outcomes in women with unexplained infertility undergoing intrauterine insemination: a retrospective single-center cohort study and meta-analysis

Introduction

Infertility affects 8-12% of couples worldwide, with 15-30% classified as unexplained infertility (UI). Thyroid autoimmunity (TAI), the most common autoimmune disorder in women of reproductive age, may impact fertility and pregnancy outcomes. However, the underlying mechanism is unclear. This study focuses on intrauterine insemination (IUI) and its potential association with TAI in UI patients. It is the first meta-analysis following a comprehensive literature review to improve result accuracy and reliability.

Methods

Retrospective cohort study analyzing 225 women with unexplained infertility, encompassing 542 cycles of IUI treatment. Participants were categorized into TAI+ group (N=47, N= 120 cycles) and TAI- group (N=178, N= 422 cycles). Additionally, a systematic review and meta-analyses following PRISMA guidelines were conducted, incorporating this study and two others up to June 2023, totaling 3428 IUI cycles.

Results

Analysis revealed no significant difference in independent variables affecting reproductive outcomes. However, comparison based on TAI status showed significantly lower clinical pregnancy rates (OR: 0.43, P= 0.028, 95%CI: 0.20-0.93) and live birth rate (OR: 0.20, P= 0.014, 95%CI: 0.05 ~ 0.71) were significantly lower than TAI- group. There was no significant difference in pregnancy rate between the two groups (OR: 0.61, P= 0.135, 95%CI: 0.32-1.17). However, the meta-analysis combining these findings across studies did not show statistically significant differences in clinical pregnancy rates (OR:0.77, P=0.18, 95%CI: 0.53-1.13) or live birth rates (OR: 0.68, P=0.64, 95%CI: 0.13-3.47) between the TAI+ and TAI- groups.

Discussion

Our retrospective cohort study found an association between TAI and reduced reproductive outcomes in women undergoing IUI for unexplained infertility. However, the meta-analysis incorporating other studies did not yield statistically significant associations. Caution is required in interpreting the relationship between thyroid autoimmunity and reproductive outcomes. Future studies should consider a broader population and a more rigorous study design to validate these findings. Clinicians dealing with women with unexplained infertility and TAI should be aware of the complexity of this field and the limitations of available evidence.

Hashimoto's Thyroiditis Negatively Influences Intracytoplasmic Sperm Injection Outcome in Euthyroid Women on T4 Substitution Therapy: A Retrospective Study

OBJECTIVE

The objective of this study was to analyze the impact of thyroid autoimmunity (TAI) on reproductive outcome parameters of intracytoplasmic sperm injection (ICSI) cycles as compared to TAI-negative ICSI cycles.

DESIGN

In this single in vitro fertilization (IVF) center retrospective study, 86 infertile women with elevated thyroid peroxidase or TGAb levels, but euthyroid after thyroxine replacement (study group), were compared to 69 female patients with no thyroid abnormalities (controls). Following ICSI treatment fertilization rate (FR), clinical pregnancy rate (CPR), miscarriage rate (MR), and live birth rate (LBR) were analyzed.

MATERIALS, SETTING, METHODS

All subjects with various infertility factors were treated with ICSI in university-based IVF center. Patients in the study group received thyroxine replacement and were euthyroid at IVF treatment. Before the IVF cycles, endocrinological parameters were uniformly assessed: thyroid function and antibodies, reproductive hormones (anti-Müllerian hormone [AMH], follicular stimulating hormone [FSH], luteinizing hormone, E2, PRL, testosterone, DHEAS, 17-OHP, AD) and OGTT (0-60-120 min glucose and insulin). Following descriptive comparison of laboratory parameters, age-adjusted analyses of FR, CPR, MR, and LBR were performed.

RESULTS

TAI-positive women were older (mean age 35.31 ± 4.95 vs. 32.15 ± 4.87 years; p = 0.002), had higher FSH (8.4 ± 3.4 vs. 7.4 ± 2.32 U/L; p = 0.024), higher E2 (53.94 ± 47.61 vs. 42.93 ± 18.92 pg/mL; p = 0.025) levels, while AMH (2.88 ± 2.62 vs. 3.61 ± 1.69 ng/mL; p = 0.0002) was lower. There were no differences in TSH levels (1.64 ± 0.96 vs. 1.66 ± 0.65 µIU/mL; p = 0.652) between the two groups. FT3 (2.63 ± 0.58 vs. 2.98 ± 0.55 pg/mL; p = 0.002) was lower and FT4 (1.3 ± 0.29 vs. 1.13 ± 0.21 ng/dL; p = 0.0002) was higher in the TAI-positive group, reflecting clinically irrelevant differences. Egg cell counts (6 ± 3.8 vs. 7.5 ± 3.95; p = 0.015) were lower in TAI and remained so following age adjustment. Although the overall ICSI FR did not differ (62.9% vs. 69.1%, p = 0.12), it was lower for patients under 35 with TAI showing decreasing differences in line with age. The CPR (36.04% vs. 69.56%; p < 0.001) and LBR (23.25% vs. 60.86%; p < 0.001) were lower, the MR (35.48% vs. 12.5%; p = 0.024) was higher in the TAI group, and these differences remained after age adjustment.

LIMITATIONS

Since the higher age of the study group may interfere with the effect of TAI, age adjustment calculations were necessary to perform to eliminate this confounding factor.

CONCLUSION

Despite optimal thyroid supplementation in clinical or subclinical hypothyroidism, the presence of TAI negatively influences CPR and is connected to a higher MR, thus resulting in a lower LBR after ICSI. Decreased FR with ICSI in TAI patients may also contribute to poorer outcomes, especially in younger women.

Elevated Thyroglobulin Antibody Level is Associated with Decreased Anti-Müllerian Hormone in Women of Reproductive Age

Purpose

Women with Hashimoto's thyroiditis (HT) have an increased risk of ovarian insufficiency. However, whether thyroid antibodies affect the ovarian reserve remains controversial. The aim of this study was to explore the possible relationship between anti-Müllerian hormone (AMH) and thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb) levels in women of reproductive age.

Methods

A total of 483 women between 18 and 45 years old who had their TPOAb, TgAb, thyroid-stimulating hormone (TSH), free thyroxine (FT4), and AMH levels measured on the same day were enrolled in this study. The levels of TSH, FT4, TPOAb, and TgAb, the prevalence of overt and subclinical hypothyroidism, and the positive rate of TPOAb and TgAb were compared between patients with low (below the 10th percentile), normal (10th to 90th percentile), and high (higher than the 90th percentile) AMH levels.

Results

The median AMH level was 1.72 (0.33-4.27) ng/mL. A total of 9.9% of patients had low AMH levels. The TgAb levels and the prevalence of TgAb positivity were higher in the low AMH group (37.62 (13.10-232.68) IU/mL, 35.42%) than in the normal (12.46 (10.0-67.04) IU/mL, 19.59%) and high (13.61 (10.0-95.74) IU/mL, 23.4%) AMH groups (p=0.001, p=0.040, respectively). Serum AMH levels were inversely correlated with TgAb levels (r = -0.114, p=0.013).

Conclusion

The AMH of women of reproductive age is affected by HT. Furthermore, women with the lowest AMH level had higher levels of TgAb and a positive rate of TgAb, and high TgAb levels may cause autoimmune damage to the ovaries.

TPOAb positivity can impact ovarian reserve, embryo quality, and IVF/ICSI outcomes in euthyroid infertile women

The aim of this study was to investigate the effects of positive anti-thyroid peroxidase (TPO) antibodies on fertility, embryo quality, and pregnancy outcomes in women with normal thyroid function. A cross-sectional study of 1223 infertile women who received assisted reproductive technology (ART) treatment for the first time was conducted at our hospital from January 2019 to March 2022. Overall, 263 infertile women were included, comprising 263 cycles and 1813 embryos, and were divided into a positive group and a control group based on TPO antibody levels. The positive group was further divided into two subgroups according to the median antibody titer, and the therapeutic indices and pregnancy outcomes for each group were compared. The results showed that the AMH level in the positive group was significantly lower than that in the control group (2.37 (1.26-3.63) ng/ml vs. 3.54 (1.74-5.41) ng/ml, p < 0.001). The high-quality embryo rate (40.04% vs. 45.49%, p = 0.034) and live birth rate (23.26% vs. 36.16, p = 0.035) of the positive group were lower than those of the control group; the miscarriage rate was higher than that of the control group (37.50% vs. 17.95%, p = 0.035). The live birth rate in the low-titer group was significantly higher than that in the high-titer group (32.56% vs. 13.95%, p = 0.041). Studies have shown that positive anti-thyroid peroxidase antibodies are associated with a decreased ovarian reserve and decreased embryo quality. High titers of anti-thyroid peroxidase antibodies can reduce the live birth rate.

Comparisons of conventional in vitro fertilization versus intracytoplasmic sperm injection in women with thyroid autoimmunity and non-male factor infertility, a propensity score matching analysis

The aim of the study is to compare the outcomes between the insemination methods of conventional in vitro fertilization and intracytoplasmic sperm injection in infertile women with thyroid autoimmunity and non-male factor infertility. This was a retrospective cohort study which included women with thyroid autoimmunity and non-male factor infertility. Reproductive outcomes such as embryo development parameters and clinical outcomes were compared between the two groups. The propensity score matching was applied to balance the general characteristics with significant differences between the two groups. Generalized estimating equations were used to explore the impact of ICSI on the embryo development potential of the inseminated oocytes. Sensitivity analysis using E-values was used to account for unknown confounders. After 1:2 propensity score matching, the general characteristics were all comparable. The good cleavage embryo rate, blastocyst utilization rate, and good blastocyst rate were significantly lower in the intracytoplasmic sperm injection group than those in the conventional in vitro fertilization group. After controlling for the confounding factors, intracytoplasmic sperm injection was significantly negatively associated with development of usable blastocysts and good blastocysts, while showed no impact on fertilized oocytes, usable cleavage embryos and good cleavage embryos. Although limited by the limited sample size, there were comparable clinical and obstetrical outcomes between conventional in vitro fertilization and intracytoplasmic sperm injection groups. Intracytoplasmic sperm injection neither improved the embryo development potential nor increased the clinical pregnancy and live birth rates compared to conventional in vitro fertilization in the studied population. Prospective studies that randomly divide the studied population in two the two groups and compare the reproductive outcomes are warranted.

Endocrine factors associated with infertility in women: an updated review

INTRODUCTION

Infertility is defined as the inability to conceive after unprotected sexual intercourse for at least 12 consecutive months. Our objective is to present an updated narrative review on the endocrine causes of infertility in women.

AREAS COVERED

A comprehensive review was conducted using Scielo, Scopus, and EMBASE databases, comprising 245 articles. The pathophysiology of infertility in women was described, including endocrinopathies such as hypothalamic amenorrhea, hyperprolactinemia, polycystic ovary syndrome, primary ovarian insufficiency, obesity, thyroid dysfunction, and adrenal disorders. The diagnostic approach was outlined, emphasizing the necessity of hormonal studies and ovarian response assessments. Additionally, the treatment plan was presented, commencing with non-pharmacological interventions, encompassing the adoption of a Mediterranean diet, vitamin supplementation, moderate exercise, and maintaining a healthy weight. Subsequently, pharmacological treatment was discussed, focusing on the management of associated endocrine disorders and ovulatory dysfunction.

EXPERT OPINION

This comprehensive review highlights the impact of endocrine disorders on fertility in women, providing diagnostic and therapeutic algorithms. Despite remaining knowledge gaps that hinder more effective treatments, ongoing research and advancements show promise for improved fertility success rates within the next five years. Enhanced comprehension of the pathophysiology behind endocrine causes and the progress in genetic research will facilitate the delivery of personalized treatments, thus enhancing fertility rates.

Polycystic ovary syndrome and thyroid disorder: a comprehensive narrative review of the literature

Background

Published data on the relationship between polycystic ovary syndrome (PCOS) and thyroid dysfunction are sparse and confusing.

Objective

To comprehensively review data available in the literature regarding the relationship between PCOS and the thyroid function, and its abnormalities.

Methods

Nine main areas of interest were identified and analyzed according to the available evidence: 1) Evaluation of thyroid function for PCOS diagnosis; 2) Epidemiology data on thyroid function/disorders in patients with PCOS, and vice versa; 3) Experimental data supporting the relationship between thyroid function/disorders and PCOS; 4) Effects of thyroid function/disorders on PCOS features, and vice versa; 5) Effect of thyroid alterations on the cardiometabolic risk in women with PCOS; 6) Effect of thyroid abnormalities on reproductive outcomes in women with PCOS; 7) Relationship between thyroid function/abnormalities in patients with PCOS who are undergoing fertility treatment; 8) Effect of treatments for thyroid diseases on PCOS; and 9) Effect of treatments for PCOS on thyroid function. An extensive literature search for specific keywords was performed for articles published from 1970 to March 2023 using PubMed and Web of Science. Data were reported in a narrative fashion.

Results

PCOS is a diagnosis of exclusion for which diagnosis is possible only after excluding disorders that mimic the PCOS phenotype, including thyroid dysfunctions. However, the tests and the cutoff values used for this are not specified. Many experimental and clinical data suggest a relationship between perturbations of the thyroid function and PCOS. Direct and unequivocal evidence on the effects of thyroid function/disorders on PCOS features are lacking. High thyroid-stimulating hormone levels and subclinical hypothyroidism may be associated with significant worsening of several intermediate endpoints of cardiometabolic risk in women with PCOS. Thyroid abnormalities may worsen reproductive outcomes, especially in patients undergoing fertility treatment. To date, there are no data demonstrating the efficacy of thyroid medications on fertility and cardiometabolic risk in women with PCOS. Lifestyle modification changes, metformin, and vitamin D seem to improve thyroid function in the general population.

Conclusion

PCOS and thyroid disorders are closely related, and their coexistence may identify patients with a higher reproductive and metabolic risk. Regular screening for thyroid function and thyroid-specific autoantibodies in women with PCOS, particularly before and during pregnancy, is highly recommended.

Metabolomic analysis of follicular fluid from women with Hashimoto thyroiditis

Hashimoto thyroiditis is an autoimmune disease characterized by hypothyroidism and a high level of anti-thyroid autoantibodies. It has shown to negatively impact female fertility; however, the mechanisms are unclear. Ovarian follicular fluid appears to be the key to understanding how Hashimoto thyroiditis affecst fertility. Thus, we aimed to evaluated the metabolic profile of follicular fluid and antithyroid autoantibody levels in the context of Hashimoto thyroiditis. We collected follicular fluid from 61 patients, namely 38 women with thyroid autoantibody positivity and 23 women as negative controls, undergoing in vitro fertilization treatment. Follicular fluid samples were analyzed using metabolomics, and thyroid autoantibodies were measured. Fifteen metabolites with higher concentrations in the follicular fluid samples from Hashimoto thyroiditis were identified, comprising five possible affected pathways: the glycerophospholipid, arachidonic acid, linoleic acid, alpha-linolenic acid, and sphingolipid metabolism pathways. These pathways are known to regulate ovarian functions. In addition, antithyroglobulin antibody concentrations in both serum and follicular fluid were more than tenfold higher in women with Hashimoto thyroiditis than in controls. Our data showed that the metabolic profile of follicular fluid is altered in women with Hashimoto thyroiditis, suggesting a potential mechanistic explanation for the association of this disease with female infertility.

Impact of thyroid autoimmunity on pregnancy outcomes in euthyroid women following fresh/frozen-thawed embryo transfer

OBJECTIVE

To investigate whether thyroid autoimmunity (TAI) is associated with assisted reproductive technology (ART) outcomes in euthyroid women undergoing fresh embryo transfer (ET) and frozen-thawed embryo transfer (FET).

DESIGN

A retrospective cohort study. Pregnancy and neonatal outcome after fresh ET or FET were compared between the positive and negative thyroid autoimmune antibody groups.

PATIENTS

A total of 5439 euthyroid women who started their ART cycle at our centre between 2015 and 2019 were included.

RESULTS

The thyroid antibody positive group had a greater mean age than the thyroid antibody negative group (32(29,35) vs. 31(28,34), p < .001). Women with positive thyroid antibody presented with a higher prevalence of diminished ovarian reserve (DOR) (9.1% vs. 7.1%, p = .026) and lower number of oocyte retrieved (9(5,15) vs. 10(6,15), p = .020), but difference was not significant after adjusting for age. The pregnancy rate, live birth rate, pregnancy loss rate, preterm delivery rate and low birthweight rate between the thyroid antibody positive and thyroid antibody negative groups were comparable both in fresh ET cycles and FET cycles. Subanalysis of the treatment outcomes when using a stricter threshold of TSH of 2.5 mIU/L showed no difference to that achieved when using an upper limit of 4.78 mIU/L.

CONCLUSIONS

The present study reveals that patients with anti-thyroid peroxidase antibodies (TPOAbs) and/or antithyroglobulin antibodies (TgAbs) showed no significant differences in pregnancy outcomes following fresh ET and FET when compared with patients with negative thyroid antibodies.

Thyroid Autoimmunity Is Not Associated with Embryo Quality or Pregnancy Outcomes in Euthyroid Women Undergoing Assisted Reproductive Technology in China

Background: Studies have shown that thyroid autoimmunity (TAI) is associated with increased risks of adverse pregnancy outcomes. The aim of this study was to investigate the associations between TAI and embryo quality in euthyroid women undergoing in vitro fertilization or intracytoplasmic sperm injection (IVF/ICSI). Methods: This retrospective cohort study included euthyroid infertile women with and without TAI (defined as a serum thyroperoxidase concentration ≥34 IU/mL or a thyroglobulin concentration ≥115.0 IU/mL) who underwent their first complete IVF/ICSI treatment cycles at a tertiary referral center between April 2016 and February 2022. Embryo quality measurements and clinical outcomes were compared between women with (TAI positive) and without TAI (TAI negative). The high-quality cleavage embryo rate and cumulative live birth rate (cLBR) were the primary outcomes. Results: A total of 499 TAI-positive and 2945 TAI-negative women were included in this study, and their mean (standard deviation) ages were 31.6 (4.5) and 30.9 (4.4) years, respectively (p = 0.001). The overall analysis showed no significant differences between TAI-negative and TAI-positive women in the high-quality cleavage embryo rate (n/N: 11,139/22,553 vs. 1971/3820; adjusted rate: 52.8% vs. 53.4%, p = 0.66) and cLBR (1917/2945 vs. 327/499; 53.4% vs. 56.2%, p = 0.31). Moreover, no significant differences were observed between TAI-negative and TAI-positive women in the rates of oocyte retrieval (35,078/51,978 vs. 5853/8628; 69.1% vs. 69.4%; p = 0.65), fertilization (23,067/34,197 vs. 3902/5728; 61.1% vs. 62.2%, p = 0.34), embryo utilization (18,233/22,553 vs. 3156/3820; 80.2% vs. 80.8%, p = 0.61), blastocyst formation (7051/13,721 vs. 1192/2330; 48.5% vs. 48.4%, p = 0.97), and high-quality blastocysts (4819/13,721 vs. 799/2330; 29.9% vs. 29.4%, p = 0.73). Furthermore, no significant differences were observed between TAI-negative and TAI-positive women in the clinical pregnancy rate (1524/2808 vs. 248/482; 46.7% vs. 44.6%, p = 0.40), early pregnancy loss rate (156/1524 vs. 23/248; 13.5% vs. 11.5%, p = 0.44), and LBR (1338/2808 vs. 218/482; 37.4% vs. 36.0%, p = 0.55) of the first transfer cycle. Conclusions: This study demonstrated that TAI in women was not associated with embryo quality or the cLBR following IVF/ICSI. Future large studies are warranted to confirm these findings.

Thyroid autoimmunity and pregnancy in euthyroid women

Women with thyroid autoimmunity (TAI), predominately characterized by increased levels of thyroid peroxidase antibody (TPOAb), are at risk for developing pregnancy related complications. In this review, we discuss the importance of TAI during natal and perinatal stages. Before pregnancy, TAI is associated with higher mean serum TSH levels and certain causes of subfertility. During pregnancy, TAI increases the risk of an insufficient response of the thyroid to an increasing strain induced by pregnancy, and consequently (subclinical) hypothyroidism might develop. Euthyroid women with TAI have a higher rate of maternal and foetal complications, but it seems that causality cannot be pinned down to thyroid dysfunction alone. Almost half of the women known with TAI prior to pregnancy will also develop post-partum thyroiditis (PPT). However, any relation between PPT and post-partum depression remains uncertain. More research is required to explain possible associations between TAI and pregnancy morbidities, and studies should focus on a better understanding of TAI as such. Given the many unanswered questions, at present, it is not recommended to screen all (potentially) pregnant women for the presence of TAI.

Impact of Antithyroperoxidase Antibodies (Anti-TPO) on Ovarian Reserve and Early Embryo Development in Assisted Reproductive Technology Cycles

Autoimmune thyroid disease (AITD) is one of the most common endocrinopathies and is more prevalent in women. It becomes evident that the circulating antithyroid antibodies that often follow AITD have effects on many tissues, including ovaries, and therefore that this common morbidity might have an impact on female fertility, the investigation of which is the aim of the present research. Ovarian reserve, ovarian response to stimulation and early embryo development in infertile patients with thyroid autoimmunity were assessed in 45 women with thyroid autoimmunity and 45 age-matched control patients undergoing infertility treatment. It was demonstrated that the presence of anti-thyroid peroxidase antibodies is associated with lower serum anti-Müllerian hormone levels and antral follicle count. Further investigation revealed the higher prevalence of sub-optimal response to ovarian stimulation in TAI-positive women, lower fertilization rate and lower number of high-quality embryos in this group of patients. The cut-off value for follicular fluid anti-thyroid peroxidase antibody affecting the above-mentioned parameters was determined to be 105.0 IU/mL, highlighting the necessity of closer monitoring in couples seeking infertility treatment with ART.

Anti-thyroid antibodies and underlying generalized immunologic aberrations in patients with reproductive failures

The link between autoimmune thyroid diseases and reproductive failures, including implantation failure and pregnancy loss, has been attracted a great deal of attention in the last two decades. In this regard, a considerable progress has been achieved in understanding the etiopathogenesis of the adverse pregnancy consequences related to the presence of anti-thyroid antibodies, however, the exact action mechanisms of these antibodies are not fully comprehended. Thyroid peroxidase antibodies (TPOAbs), thyroglobulin antibodies (TgAbs) and TSH receptor antibodies (TRAbs) are the anti-thyroid antibodies which are present in autoimmune thyroid disorder (AITD) patients, such as Hashimoto's thyroiditis. In this condition, the thyroid hormones production, which are essential for normal implantation and pregnancy, are disrupted, and compromise the embryo or fetus development. In addition, a hypothesis suggests that there is underlying generalized immune abnormalities behind the presence of these antibodies. On the other hand, similar immunologic aberrations have been observed in thyroid autoimmunity and reproductive complications, which are postulated to be the proper answer for the scientists who seek for the pathophysiology behind the presence of these antibodies. Elevated inflammatory responses and decreased immunoregulatory actions, seem to be the main interfering pathologic factors in maternal tolerance toward fetus. In addition, cross reactivity of these antibodies with antigenic determinants of egg, embryo and placenta is another suggested mechanism, causing implantation and pregnancy complications. The ability of anti-thyroid antibodies in passing through the placental barrier and affecting the fetal thyroid gland, makes them more threatening for maintenance of a pregnancy.

Follitropin Alpha for assisted reproduction: an analysis based on a non-interventional study in Greece

OBJECTIVE

To conduct an economic evaluation estimating the cost per live birth after controlled ovarian stimulation (COS) using Follitropin Alpha (Gonal-F), in the Greek National Health System setting. A secondary objective was to predict the live birth rateof the In Vitro Fertilization (IVF) procedure.

METHODS

A single arm, multi-center, prospective, non-interventional study was conducted on which economic, efficacy and safety data were collected by six of the largest IVF centers. The participants were 350 female patients. Three statistical methods were employed for the analysis of the study outcomes, namely (a) Generalized Linear Modeling for the estimation of the costs of IVF treatment, (b) multivariable logistic regression and (c) an Artificial Neural Network (ANN) model for live birth prediction.

RESULTS

The mean total cost of IVF therapy per patient was estimated at €3728 (95% CI: €3679-€3780), while the total cost per live birth was €14,872 (95% CI: €12,441-€17,951). The live birth rate after 3 complete IVF cycles was estimated at 22.9%, while the percentage of those suffering from OHSS was limited at 0.57%. In logistic regression, the Ovarian Sensitivity Index (OSI) was a factor found to be positively associated with live birth (OR 7.39, 95% CI: 1.84-29.71). For the ANN, important predictors included number of gestational sacs and the duration of infertility.

CONCLUSION

The present study constitutes the largest single-arm study based on real data in Greece to date. The cost of IVF treatment and the cost per live birth are not insignificant in this NHS setting. The live birth rate, cost per oocyte, and the cost per live birth are in line with literature. OSI was a main contributing factor to the accurate prediction of the live birth rate, while age and BMI were found to be negatively correlated.

B cells from anti-thyroid antibody positive, infertile women show hyper-reactivity to BCR stimulation

Anti-thyroid antibody (ATA) positivity affects 1 out of 9 women in childbearing age and presents a significant risk for infertility. Emerging evidence indicates that alterations in the B cell receptor induced calcium (Ca2+) signaling could be key in the development of autoimmunity. We aimed to investigate the Ca2+ flux response of B lymphocyte subsets to BCR stimulation in Hashimoto’s thyroiditis and related infertility. We collected peripheral blood samples from ATA+, infertile, euthyroid patients (HIE), hypothyroid, ATA+ patients before (H1) and after levothyroxine treatment (H2), and age-matched healthy controls (HC). All B cell subsets of ATA+, infertile, euthyroid patients showed elevated basal Ca2+ level and hyper-responsivity to BCR ligation compared to the other groups, which could reflect altered systemic immune function. The Ca2+ flux of hypothyroid patients was similar to healthy controls. The levothyroxine-treated patients had decreased prevalence of CD25+ B cells and lower basal Ca2+ level compared to pre-treatment. Our results support the role of altered Ca2+ flux of B cells in the early phase of thyroid autoimmunity and infertility.

Pre-Conceptional Anti-Thyroid Antibodies and Thyroid Function in Association with Natural Conception Rates

Thyroid functioning is an integral part of the endocrine system that supports conception and pregnancy. Frequent consumption of seafood and iodine by Japanese people may adversely affect their thyroid function. Thus, in this study, we aimed to analyze the associations between iodine intake, thyroid hormones, autoimmunity, and natural conception rates in Japanese women trying to conceive their first child. A prospective study of 24 weeks targeted 80 women with no history of infertility, who did not plan to undergo fertility treatment. Concentrations of urinary iodine concentration and thyroid biomarkers in the serum at enrollment were measured. Thirty-five women naturally conceived during the follow-up. The median (inter-quartile range) urinary concentration of iodine was 297 (165, 500) μg/L. Free triiodothyronine (T3) and free thyroxin (T4) negatively correlated with urinary iodine concentrations. Women with anti-thyroid peroxidase (anti-TPO) ≥ 16 IU/mL had lower conception rates (hazard ratio: 0.28, 95% confidence interval, 0.08-0.92) compared with those with anti-TPO < 16 IU/mL, after adjusting for age and coital frequency. None of anti-thyroglobulin antibody, free T3, free T4, or thyroid-stimulating hormone showed significant associations with conception rate after adjusting for age and coital frequency. The negative association between thyroid autoimmunity and natural conception rates warrants further investigation.

Opportunities and Limits of Conventional IVF versus ICSI: It Is Time to Come off the Fence

Conventional IVF (c-IVF) is one of the most practiced assisted reproductive technology (ART) approaches used worldwide. However, in the last years, the number of c-IVF procedures has dropped dramatically in favor of intracytoplasmic sperm injection (ICSI) in cases of non-male-related infertility. In this review, we have outlined advantages and disadvantages associated with c-IVF, highlighting the essential steps governing its success, its limitations, the methodology differences among laboratories and the technical progress. In addition, we have debated recent insights into fundamental questions, including indications regarding maternal age, decreased ovarian reserve, endometriosis, autoimmunity, single oocyte retrieval-cases as well as preimplantation genetic testing cycles. The “overuse” of ICSI procedures in several clinical situations of ART has been critically discussed. These insights will provide a framework for a better understanding of opportunities associated with human c-IVF and for best practice guidelines applicability in the reproductive medicine field.

Impact of Thyroid Autoimmunity on Assisted Reproductive Technology Outcomes and Ovarian Reserve Markers: An Updated Systematic Review and Meta-Analysis

Background: Thyroid autoimmunity (TAI) has a high prevalence among women of reproductive age. Investigating its possible impact on ovarian function and fertility is, thus, of utmost relevance. The aim of this systematic review and meta-analysis was to elucidate the effect of TAI on both assisted reproductive technology (ART) outcomes and ovarian reserve. Methods: This systematic review and meta-analysis was restricted to two groups of research articles investigating the association between TAI and: (1) autologous ART outcomes (i.e., fertilization rate [FR], implantation rate, clinical pregnancy rate [CPR], miscarriage rate, and live birth rate), (2) markers of ovarian reserve (i.e., anti-Müllerian hormone, basal follicle stimulating hormone, antral follicle count, and number of oocytes retrieved). Studies including women affected by overt hypo/hyperthyroidism were excluded. Relevant studies were identified by a systematic search in PubMed, MEDLINE, ClinicalTrials.gov, Embase, and Scopus, from database inception to May 1, 2022. Results: From a total of 432 identified publications, 22 studies were included in Group 1 and 26 studies in Group 2. The presence of TAI was associated with a higher risk of miscarriage (7606 participants, odds ratio [OR] 1.52, confidence interval [CI 1.14-2.01], p = 0.004, I² = 53%), lower chance of embryo implantation (7118 participants, OR 0.72, [CI 0.59-0.88], p = 0.001, I² = 36%), and live birth (11417 participants, OR 0.73, [CI 0.56-0.94], p = 0.02, I² = 71%). These associations were no longer observed in a subgroup analysis of patients who exclusively underwent intracytoplasmic sperm injection (ICSI). The FR and CPR as well as the mean values of surrogate markers of oocyte quantity appeared not to be affected by TAI. Conclusions: This data synthesis suggest a higher risk of adverse ART outcomes in women with positive TAI. However, the reliability of these findings is hampered by the relatively low quality of the evidence and significant heterogeneity in many of the meta-analyses. The possible protective effect of ICSI is promising but should be confirmed in controlled prospective clinical trials. PROSPERO Registration ID: CRD42021236529.

Effects of controlled ovarian stimulation on thyroid function during pregnancy

Controlled ovarian stimulation (COS) is a major component of assisted reproductive technologies. Clinically, it has been observed that, some women experience changes in thyrotropin levels following COS, which then bring about subclinical hypothyroidism and may adversely affect conception. Studies have also shown that the specific degree as well as the tendency of changes in thyroid function vary with differences in thyroid function before pregnancy, thyroid autoimmunity, the COS regimen, and the observation time point. However, the associated pathophysiological mechanism of the effects of COS on pregnancy has not yet been fully elucidated. This may be because increased estradiol levels, caused by COS, induce increased levels of thyroxine-binding globulin, resulting in a decrease in free thyroxine (FT4) level and an increase in TSH level. Conversely, it has also been observed that human chorionic gonadotropin (hCG) can act directly on thyroid cells, exerting opposite effects on FT4 and TSH levels. Additionally, the effects of COS on thyroid function may be more pronounced, especially in women with autoimmune thyroid disease or thyroid dysfunction before pregnancy, ultimately leading to subclinical hypothyroidism. Here, we review recent research progress regarding the effects of COS on thyroid function during pregnancy.

The Relationships among Plasma Fetuin-B, Thyroid Autoimmunity, and Fertilization Rate In Vitro Fertilization and Embryo Transfer

OBJECTIVE

The objective of the study is to investigate the relationships between fetuin-B, thyroid autoimmunity (TAI), and pregnancy outcomes in women undergoing in vitro fertilization and embryo transfer (IVF-ET). Design, Patients, and Measurements. In this prospective study, 180 women who were preparing for pregnancy with IVF-ET were included. There were 120 women with TAI positive and 60 negative controls matched with age and BMI.

RESULTS

The 180 women had mean ± SD age of 31.4 ± 4.0 years, with a mean ± SD BMI of 21.0 ± 1.6 kg/m². There was a significant difference in the level of fetuin-B in women with TAI positive compared with TAI negative group (65.2 ± 18.5 vs. 76.4 ± 25.1, P=0.001). Fetuin-B had a negative relationship with thyroid antibodies even after adjusting for other variables (OR (95%CI) = 0.98 (0.96-0.99), P=0.002). Compared with women with TAI negative, those with TAI positive had a significantly higher risk of low fertilization (20.0% vs. 6.7%; P=0.035). And we found no difference in terms of pregnancy, abortion, implantation, and live birth rate between the two groups. Logistic regression analysis showed that both fetuin-B and TAI were the independent factors to lead the low fertilization of IVF-ET (OR (95%CI) = 0.96 (0.94-0.99) and 4.084 (1.39-15.30), P=0.004 and 0.019, respectively).

CONCLUSION

Fetuin-B was significantly associated with TAI and low fertilization rate in women undergoing IVF-ET. Decreased fetuin-B in women with TAI may be the underlying reason for the lower IVF-ET success rate.

Thyroid Autoimmunity in Female Infertility and Assisted Reproductive Technology Outcome

The regulation of the female reproductive system is one of the most relevant actions of thyroid hormones. Adequate thyroid hormones production is essential for normal menstrual function and fertility as well as for the successful maintenance of pregnancy. The relationship between reproductive failure and thyroid disorders is particularly relevant and attracts attention worldwide. Thyroid autoimmunity (TAI), defined by the presence of circulating antithyroid antibodies targeting thyroid peroxidase (TPOAb) and thyroglobulin (TgAb), is prevalent among women of reproductive age and is the most frequent cause of thyroid dysfunction. Several studies addressed the association between TAI, thyroid function, and fertility as well as pregnancy outcome after spontaneous or assisted conception. Infertility, miscarriages, and fetal-maternal complications are described in overt autoimmune hypothyroidism. More debatable is the role of mild thyroid dysfunction, mainly subclinical hypothyroidism (SCH), and TAI in the absence of thyroid dysfunction in infertility and reproductive outcome. Assisted reproductive technology (ART) has become an integral element of care for infertility. Women with TAI undergoing ART are of particular interest since they carry a higher risk of developing hypothyroidism after the ovarian stimulation but whether TAI, in absence of thyroid dysfunction, adversely affects ART outcome is still controversial. Likewise, the role of levothyroxine (LT4) in improving fertility and the success of ART in euthyroid women with TAI is unclear. This review discusses the role of TAI, in the absence of thyroid dysfunction, in infertility and in ART outcome.

Thyroid autoimmunity and reproduction: Bidirectional relationship that continues to intrigue

Today, infertility is not only a serious health but also a psycho-social problem, one that is on the rise in the world. Thyroid autoimmunity (TAI) is the most common disease of the thyroid gland in the reproductive period, which can affect spontaneous conception as well as conception through assisted reproduction technology (ART), but also the maintenance of healthy pregnancy. It can also cause numerous maternal and fetal complications. There is a wide array of publications on the topic of the mechanisms of association between TAI and reproduction, with the question of whether thyroid autoantibodies are solely tissue-specific antibodies, whether and when to start levothyroxine treatment, and that we require more fundamental research on the direct effect of thyroid autoantibodies starting from folliculogenesis to embryogenesis and implantation as well as the post-implantation embryo development, but also the composition of the follicular fluid as a microenvironment of enormous importance for the maturation of the oocytes which thyroid autoantibodies reach via the blood-follicle barrier.

Thyroid autoimmunity and its negative impact on female fertility and maternal pregnancy outcomes

Thyroid autoimmunity (TAI) is commonly defined as the presence of thyroperoxidase antibodies (TPOAbs) and/or thyroglobulin antibodies (TgAbs), which predisposes an individual to hypothyroidism. TAI affects nearly 10% of women of reproductive age and evokes great interest from clinicians because of its potentially negative impact on female fertility and pregnancy course. In this mini-review, we review the current literature concerning the influence of TPOAb or TPOAb/TgAb positivity without thyroid dysfunction on reproduction. TAI may negatively affect female fertility; several studies have found an increased prevalence of TAI in infertile women, especially in those with unexplained infertility and polycystic ovary syndrome. According to some observations, TAI might also be connected with premature ovarian insufficiency and endometriosis. The relationship between TAI and an increased risk of pregnancy loss is well documented. The pathophysiological background of these observations remains unclear, and researchers hypothesize on the direct infiltration of reproductive organs by thyroid antibodies, co-existence of TAI with other autoimmune diseases (either organ specific or systemic), immunological dysfunction leading to inhibition of immune tolerance, and relative thyroid hormone deficiency. Interestingly, in the current literature, better outcomes of assisted reproductive technology in women with TAI have been reported compared with those reported in earlier publications. One plausible explanation is the more widespread use of the intracytoplasmic sperm injection method. The results of randomized clinical trials have shown that levothyroxine supplementation is ineffective in preventing adverse pregnancy outcomes in women with TAI, and future research should probably be directed toward immunotherapy.

Effect of hypothyroidism and thyroid autoimmunity on the ovarian reserve: A systematic review and meta-analysis

Background

Evidence suggests that hypothyroidism and thyroid autoimmunity (TAI) are possibly associated with ovarian dysfunction. This meta‐analysis aimed to investigate whether hypothyroidism and/or TAI affect the ovarian reserve and evaluated using the anti‐Mullerian hormone (AMH).

Methods

PubMed, EMBASE, Web of Science, and Cochrane Controlled Trials Register databases from inception to October 2020 were searched to identify relevant studies. Studies comparing the AMH levels between the control and the affected groups were included in the data synthesis. The primary endpoint in the meta‐analysis was AMH levels compared with the controls.

Main findings

Nine trials were included in the analysis. The AMH levels were significantly lower in the adults with euthyroid TAI (mean difference −0.12, [95% CI: −0.18 to −0.06]). The AMH levels tended to be lower in subclinical hypothyroidism and overt hypothyroidism than in the control group, although the differences were not significant. The AMH levels were significantly higher in the euthyroid TAI group in the adolescents (mean difference 2.51, [95% CI 1.82 to 3.21]).

Conclusion

TAI and hypothyroidism may affect the ovarian reserve. The opposite effects on AMH levels depending on age suggest that TAI may be implicated in the depletion of follicles in adults following extensive activation of primordial follicles in adolescence.

More Live Births in Primary Subfertile Intracytoplasmic Sperm Injection-Treated Women with High Normal TSH Levels

OBJECTIVES

The aim of this study was to analyze the fertility outcome in intracytoplasmic sperm injection (ICSI)-treated women across normal range thyroid-stimulating hormone (TSH) levels. Published results are inconclusive about optimal TSH levels and fertility.

DESIGN

This is a retrospective cohort study in 752 ICSI-treated women with predominantly severe male factor subfertility, starting treatment between the first of January 2008 and the first of March 2012 with a follow-up until 2014. Participants/Materials, Setting, Methods: Women aged 22-45 years with TSH 0.3-4.5 mIU/L without thyroid hormone substitution were included in Amsterdam UMC, Vrije Universiteit, Amsterdam, The Netherlands, an iodine-sufficient area. Demographic and baseline characteristics were compared between groups of patients based on TSH, using one-way ANOVA, Kruskal-Wallis ANOVA, and χ2 test. The patient was the unit of analysis: all cumulative cycles per patient were analyzed up to and including the first ongoing pregnancy. The primary outcome was a cumulative live birth rate. Clinical pregnancy rate, pregnancy loss, and ongoing pregnancy rate were secondary outcomes. The χ2 test and logistic regression were used to compare interquartile groups while adjusting for confounders. Logistic regression was used with the natural logarithm of TSH as a continuous predictor. Primary and secondary subfertile women were analyzed separately.

RESULTS

Analysis of the total cohort (n = 752) showed no difference in fertility outcomes across the normal TSH range. The cumulative live birth rate for the 4 groups of primary subfertile women (n = 455) was 76% in the upper TSH quartile compared to 56%, 60%, and 59% in the lower TSH quartiles.

LIMITATIONS

Levels of thyroxine and presence of thyroid autoimmunity were not measured in this retrospective cohort study.

CONCLUSIONS

The observation that a higher live birth rate was found in primary subfertile ICSI-treated women with high but allegedly normal TSH levels contributes to the hypothesis that in certain subfertile women in addition to a male factor, female factors such as subtle hypothyroidism and/or thyroid autoimmunity may play a role in keeping them from conception, which can be overcome by the process of ICSI.

Thyroid Autoimmunity in Adverse Fertility and Pregnancy Outcomes: Timing of Assisted Reproductive Technology in AITD Women

Thyroid autoimmunity (TAI) is prevalent in women of live-birthing age and has independently been associated with complications of fertility and pregnancy, in the case of spontaneous conception or after assisted reproductive technology (ART) treatment. However, it remains challenging to identify causation between infertility and TAI, even interventional trials looking at the impact of levothyroxine (LT4) treatment on fertility and pregnancy outcomes due to differences among study results which related to small scales, impropriate study designs, enrollment criteria of infertility cause and titer/hormone concentration measurements. Furthermore, many questions remain unsettled in ART management in AITD infertile women attempt pregnancy. Therefore, further observational and interventional trials are needed more comprehensive multiple-center, double blinded, and randomized.

Antithyroid antibodies may predict serum beta HCG levels and biochemical pregnancy losses in euthyroid women with IVF single embryo transfer

OBJECTIVE

To investigate the relationship between thyroid autoimmunity and early pregnancy serum β-HCG levels in intracytoplasmic sperm injection patients.

METHODS

The study subjects were 85 female euthyroid patients undergoing intracytoplasmic sperm injection embryo transfer cycles with GnRH antagonist treatment. Patients who received transfer of more than one embryo, those with serum TSH levels of greater than 2.5 IU/ml and subjects using levothyroxine were excluded. Normal responder patients under the age of 40 years were randomly selected from the patient files retrospectively. Subjects were divided into two groups: those with autoimmune thyroid disease (thyroid autoimmunity group; n = 39) and those without the disease (control group; n = 46).

RESULTS

The age, body mass index, trial number, total rFSH treatment dose, the number of cumulus oophorus complexes, number of metaphase II oocytes, and number of 2-pronuclei embryos were similar in the thyroid autoimmunity and control groups. Serum β-HCG levels measured on the 14th day after oocyte pickup were significantly lower in the thyroid autoimmunity group than in the control group (93.8 ± 35.8 versus 128.5 ± 55.8 mlU/ml, respectively; p < .001). The miscarriage rate was higher in the thyroid autoimmunity group than in the control group (34.4% versus 21.7%, respectively; p = .034).

CONCLUSION

We found that early-stage pregnancy serum β-HCG hormone levels among euthyroid patients undergoing intracytoplasmic sperm injection were lower in subjects with thyroid autoimmunity than in those without thyroid autoimmunity. This result, reported for the first time in the literature on euthyroid pregnant women with thyroid autoimmunity, may be predictor of early pregnancy losses in pregnant women with thyroid autoimmunity.Key messageIn intracytoplasmic sperm injection (ICSI)/IVF patients, due to lack of evidence-based data about the relationship between thyroid autoimmunity and pregnancy loss the current research was conducted. Early-stage pregnancy serum β-HCG hormone levels in euthyroid ICSI patients with thyroid autoimmunity are lower than those without autoimmunity which may be associated with early pregnancy losses.

Body Composition and Serum Anti-Müllerian Hormone Levels in Euthyroid Caucasian Women With Hashimoto Thyroiditis

Objective

Women with Hashimoto thyroiditis (HT) are characterized by increased incidence of infertility and disturbances in body composition. Serum anti-Müllerian hormone (AMH), which reflects functional ovarian reserve, is decreased in women with HT and it be related to body mass. The aim of the present study was to investigate the relation between serum levels of AMH and body composition in HT compared to control group.

Patients and Methods

We examined 85 euthyroid women: 39 subjects with HT and 46 control women. Body composition was analysed by dual-energy X-ray absorptiometry and with bioimpedance method. Serum concentrations of AMH, leptin, TSH, thyroid hormones were assessed.

Results

We observed lower serum concentration of AMH in women with HT in comparison to the control group (p=0.01), but without differences in serum concentration of leptin between studied groups (p=0.28). Women with HT were characterized by higher %body fat (p=0.01) estimated with bioimpedance method without differences in BMI, android and gynoid fat mass and visceral adipose tissue (VAT) mass estimated with DXA method when compared to the control group (all p>0.05). We found a negative relationship between serum concentration of AMH and %body fat (r=-0.38,p=0.03) in women with HT. Additionally, in HT group, the relationship between serum levels of AMH and leptin was not statistically significant (r=0.01,p=0.96). We observed a relationship between serum concentration of leptin and BMI, %body fat mass, android, gynoid and VAT mass in HT and in the control group (all p<0.01).

Conclusions

Women with HT are characterized by lower levels of AMH and it is associated with higher fat mass, independently of serum levels of leptin.

The association between subclinical hypothyroidism and TPOAb positivity with infertility in a population-based study: Tehran thyroid study (TTS)

BACKGROUND

Thyroid autoimmunity(TAI) is the most prevalent autoimmune condition in women of fertile age. There are increasing data regarding the association of thyroid dysfunction and thyroid autoimmunity with adverse pregnancy outcomes but there is no consensus regarding infertility and TPOAb positivity; thus we aimed to evaluate the association between thyroid TPOAb positivity and infertility in females and males in a population-based study (TTS).

METHODS

Cross-sectional study of 3197 female and male participants in Tehran Thyroid Study (TTS) at the framework of the Tehran Lipid and Glucose Study (TLGS). Data included biochemical measurements and a self-administered questionnaire.

RESULTS

A total of 12,823 cases in phase 4, 3719 cases (2108 female and 1611 male) were analyzed. The mean TSH of the infertile female and male was 2.52 ± 2.68 μIU/ml and 3.24 ± 10.26 μIU/ml respectively. The TPO median(IQR) of women with and without a history of infertility were 6.05 (3.30-13.96)and 6.04 (3.17-11.15);(P = 0.613), they were 5.08 (3.20-125.68) and 5.31 (3.93-125.68);(P = 0.490) in male participants, respectively. Results of crude and adjusted logistic regression analysis of the development of infertility by thyroid function and TPOAb, except for fT4 in male subjects, depicted no association between infertility and other variables in both crude and adjusted models.

CONCLUSION

Based on the result, thyroid autoimmunity was not associated with infertility in both females and males.

Thyroid autoimmunity is associated with higher risk of premature ovarian insufficiency-a nationwide Health Insurance Research Database study

STUDY QUESTION

Is thyroid autoimmunity associated with a higher risk of low ovarian reserve and POI?

SUMMARY ANSWER

Thyroid autoimmunity significantly increases the risk of POI in women.

WHAT IS KNOWN ALREADY

POI is closely related with autoimmune disease, and according to some studies, thyroid autoimmunity (TAI) may account for diminished ovarian reserve. However, no large-scale cohort study has demonstrated the association between TAI and POI.

STUDY DESIGN, SIZE, DURATION

A longitudinal population-based retrospective cohort study on the National Health Insurance Research Database (NHIRD) was designed. Since 1 March 1995, the National Health Insurance (NHI) programme in Taiwan has included 99.9% of the 23 million population of Taiwan. Patients between 1 January 2000 and 31 December 2012 were eligible for recruitment, and 21 325 subjects were analysed in our study.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Two cohorts, Hashimoto's and Grave's disease, were composed of patients with autoimmune thyroid disease between 20 and 40 years of age. The comparison cohorts consisted of patients in the NHIRD without autoimmune thyroid disease matched by age at a ratio of 1:4 in subject numbers.

MAIN RESULTS AND THE ROLE OF CHANCE

The Hashimoto's disease (HD) cohort, Grave's disease (GD) cohort and two comparison cohorts were followed up until a diagnosis of amenorrhoea, menopausal syndrome, other ovarian failure or infertility due to ovarian failure had been made. Compared statistically with the non-HD cohort, patients with HD exhibited an 89% higher risk of amenorrhoea (95% CI =1.36-2.61). The HD patients exhibited a 2.40-fold higher risk of infertility due to ovarian failure than the non-HD subjects (hazard ratio (HR)=2.40, 95% confidence interval (CI)=1.02-5.68). In comparison with the non-GD cohort, patients with GD exhibited a 68% higher risk of amenorrhoea (95% CI = 1.43-1.98) after adjustment. According to the Kaplan-Meier analysis, the cumulative incidence of amenorrhoea and menopausal syndrome was significantly higher in the TAI groups than in the control groups.

LIMITATIONS, REASONS FOR CAUTION

This is a retrospective study using ICD-9 disease code analysis to determine the statistical association between two diseases.

WIDER IMPLICATIONS OF THE FINDINGS

Given that autoimmune thyroid disease is highly associated with early diminished ovarian reserve or even premature ovarian failure or POI, the options for infertility treatment may be re-directed to more efficient methods in infertile patients diagnosed with the disease. If the ovarian reserve is normal at the time of diagnosis of thyroid autoimmune disease, close follow-up of ovarian reserve may be highly recommended.

STUDY FUNDING/COMPETING INTEREST(S)

This study is supported in part by Taiwan Ministry of Health and Welfare Clinical Trial Center, Grant Number: MOHW109-TDU-B-212-114004. The authors have no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

Glucocorticoid supplementation improves reproductive outcomes in infertile women with antithyroid autoimmunity undergoing ART: A meta-analysis

BACKGROUND

Thyroid autoimmune disease (TAI) has been verified to be related to multiple adverse pregnancy outcomes. A growing number of evidences highlight the protective roles of glucocorticoid on the treatments of TAI. This meta-analysis aimed to study whether it is beneficial to add glucocorticoid treatment in infertile women with TAI when they are undergoing assisted reproductive technology (ART).

METHODS

We conducted a systematic search in PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure (CNKI), WanFang database, Weipu China Science and Technology Journal Databases (VIP database) up to September 10, 2020. The Revman 5.3 software was utilized for data statistics. We used a random-effects model to analyze data and the odds ratio (OR) combining with 95% confidence interval (95% CI) were employed to reveal the results.

RESULTS

Three publications with 237 antithyroid antibody (ATA)-positive and 384 ATA-negative women were included in the final analysis. Overall, glucocorticoid therapy showed satisfying effects on improving clinical pregnancy rate (OR = 4.63, 95% CI [2.23, 9.58], I2 = 0.0%, P < .0001) and live birth rate (OR = 3.19, 95% CI [1.13, 9.04], I2 = 0.0%, P = .03) of ATA-positive women compared with control group. However, it seems that glucocorticoid showed no significant difference in the abortion rate (OR = 0.62, 95% CI [0.09, 4.32], I2 = 35%, P = .64) and oocyte recovery (OR = 2.26, 95% CI [-1.46, 5.99], I2 = 79%, P < .0001) between the 2 groups.

CONCLUSIONS

Glucocorticoid may improve the pregnancy outcomes of ART women with ATA positive, but there is no significant reduction in the risk of miscarriage. Due to the limited enrolled references, glucocorticoid adjuvant therapy should be applied after more randomized controlled trials.

Unraveling the Balance between Genes, Microbes, Lifestyle and the Environment to Improve Healthy Reproduction

Humans’ health is the result of a complex and balanced interplay between genetic factors, environmental stimuli, lifestyle habits, and the microbiota composition. The knowledge about their single contributions, as well as the complex network linking each to the others, is pivotal to understand the mechanisms underlying the onset of many diseases and can provide key information for their prevention, diagnosis and therapy. This applies also to reproduction. Reproduction, involving almost 10% of our genetic code, is one of the most critical human’s functions and is a key element to assess the well-being of a population. The last decades revealed a progressive decline of reproductive outcomes worldwide. As a consequence, there is a growing interest in unveiling the role of the different factors involved in human reproduction and great efforts have been carried out to improve its outcomes. As for many other diseases, it is now clear that the interplay between the underlying genetics, our commensal microbiome, the lifestyle habits and the environment we live in can either exacerbate the outcome or mitigate the adverse effects. Here, we aim to analyze how each of these factors contribute to reproduction highlighting their individual contribution and providing supporting evidence of how to modify their impact and overall contribution to a healthy reproductive status.

Thyroid function modifications in women undergoing controlled ovarian hyperstimulation for in vitro fertilization: a systematic review and meta-analysis

OBJECTIVE

To investigate the impact of controlled ovarian hyperstimulation (COH) for in vitro fertilization (IVF) on thyroid function.

DESIGN

Systematic review and meta-analysis.

SETTING

Not applicable.

PATIENT(S)

Infertile women undergoing conventional IVF or intracytoplasmic sperm injection.

INTERVENTION(S)

Systematic search of PubMed, MEDLINE, Embase, Scopus, and Web of Science from inception until November 2020. Studies could be included only if they met the following criteria: subjects were classified as euthyroid or hypothyroid; serum thyroid-stimulating hormone (TSH) and/or free thyroxine (FT4) levels were evaluated before COH; and the same thyroid function test was reassessed after COH (i.e., at the time of trigger for final follicle maturation and/or at pregnancy test).

MAIN OUTCOME MEASURE(S)

Mean difference (MD) between the serum TSH or FT4 levels assessed after COH and before COH.

RESULT(S)

In euthyroid women, the serum TSH levels assessed at the time of trigger and at the time of pregnancy test were significantly higher than those at baseline (MD: 0.69 mIU/L, 95% confidence interval [CI]: 0.30-1.08, I² = 93% and MD: 0.67, 95% CI: 0.49-0.85, I² = 72%, respectively). The serum FT4 levels did not undergo significant changes. Subanalysis confirmed an increase in the TSH level after restricting the analysis to women treated with gonadotropin-releasing hormone agonist protocols and to those who achieved pregnancy. A pronounced increase in the TSH level was observed in women treated for hypothyroidism (MD: 1.50 mIU/L, 95% CI: 1.10-1.89, I² = 0%).

CONCLUSION(S)

Pooling of the results showed a significant increase in serum TSH level in women undergoing COH for IVF. This change was particularly pronounced in women treated for hypothyroidism. New thyroid function screening strategies for women undergoing COH are warranted.

Association between thyroid autoimmunity and ovarian reserve in women with hypothyroidism

Background

The ovarian function and therefore the ovarian reserve may be compromised by the pathogenesis of autoimmune diseases of which, Hashimoto’s thyroiditis (HT) is the most common in women of reproductive age. Furthermore, a prolonged reduction in thyroid hormone concentration results in a broad spectrum of reproductive alteration. Previous reports in the literature have been controversial regarding the impact of hypothyroidism and alterations in the ovarian reserve. Thus, this prospective and comparative study aimed to evaluate the association of hypothyroidism with low ovarian reserve.

Materials and Methods

A subset of 27 patients with primary autoimmune hypothyroidism were compared to healthy women. The ovarian reserve was assessed through the anti-Mullerian hormone (AMH) and the antral follicle count (AFC).

Results

Overall, the two groups did not display significant differences in length of their menstrual cycles neither in the AMH serum levels nor the AFC.

Conclusions

No significant alteration was found in the ovarian reserve of women with HT.

Hashimoto's thyroiditis worsens ovaries in polycystic ovary syndrome patients compared to Anti-Müllerian hormone levels

BACKGROUND

The human ovary is the target of autoimmune attack in cases of autoimmune disorders, which can cause ovarian dysfunction. Due to the higher prevalence of Hashimoto's Thyroiditis (HT) in Polycystic Ovary Syndrome (PCOS) patients, we aimed to evaluate ovarian reserve and the effect of autoimmune exposure time on ovarian reserve in PCOS patients with HT by Anti-Müllerian hormone (AMH) levels.

METHODS

Forty-six PCOS patients and 46 PCOS with HT diagnosed patients who are between 18 and 35 years old were recruited for this study. Detailed medical histories were obtained from all participants. Polycystic ovary image was evaluated and antral follicles were counted by transvaginal ultrasound. Modified Ferriman Gallwey score, body mass index, waist/hip ratio of the patients were examined. Hormonal, biochemical profiles and AMH levels of the patients were evaluated during the early follicular phase. The data of both groups were statistically analyzed with SPSS 18.0.

RESULTS

20 (43.5%) patients in the PCOS group were fertile, 8 (17.4%) patients in the PCOS + HT group were fertile, fertility rate was significantly lower in PCOS + HT group. The mean AMH value was 8.8 ± 8.8 in the PCOS + HT group and 12.4 ± 8.1 in the PCOS group and it was significantly lower in the PCOS + HT group (p = 0.043). AMH values were significantly negatively correlated with anti-thyroid peroxidase antibody (anti-TPO) level and the duration of HT. There was a significant positive correlation between the anti-TPO level and the duration of HT. CONCLUSıON: We pointed out that the coexistence of PCOS and HT, two prevalent diseases of reproductive age, further diminished ovarian reserve. More exposure of the ovaries to autoantibodies can cause ovarian destruction, similar to the thyroid gland like HT. Because of all these close relations with PCOS and thyroid dysfunctions, we recommend evaluating both thyroid autoantibodies and hormone levels in PCOS patients at the first visit. Patients with PCOS + HT should be monitored more closely to determine the fertility treatment options and control premature ovarian failure (POF) table.

2021 European Thyroid Association Guideline on Thyroid Disorders prior to and during Assisted Reproduction

Severe thyroid dysfunction may lead to menstrual disorders and subfertility. Fertility problems may persist even after restoring normal thyroid function, and then an assisted reproductive technology (ART) may be a solution. Prior to an ART treatment, ovarian stimulation is performed, leading to high oestradiol levels, which may lead to hypothyroidism in women with thyroid autoimmunity (TAI), necessitating levothyroxine (LT4) supplements before pregnancy. Moreover, women with the polycystic ovarian syndrome and idiopathic subfertility have a higher prevalence of TAI. Women with hypothyroidism treated with LT4 prior to ART should have a serum TSH level <2.5 mIU/L. Subfertile women with hyperthyroidism planning an ART procedure should be informed of the increased risk of maternal and foetal complications, and euthyroidism should be restored and maintained for several months prior to an ART treatment. Fertilisation rates and embryo quality may be impaired in women with TSH >4.0 mIU/L and improved with LT4 therapy. In meta-analyses that mainly included women with TSH levels >4.0 mIU/L, LT4 treatment increased live birth rates, but that was not the case in 2 recent interventional studies in euthyroid women with TAI. The importance of the increased use of intracytoplasmic sperm injection as a type of ART on pregnancy outcomes in women with TAI deserves more investigation. For all of the above reasons, women of subfertile couples should be screened routinely for the presence of thyroid disorders.

Recent insights into the impact of immune dysfunction on reproduction in autoimmune thyroiditis

Autoimmune thyroiditis (AIT) is a common organ-specific autoimmune disease with a high incidence among women of childbearing age. Recent studies have reported that women with AIT are more susceptible to infertility, miscarriage and preterm birth. It has been investigated that abnormal changes in maternal immune system and maternal-fetal interface can dampen the immune tolerance between mother and fetus, which underlie the pathogenesis of adverse pregnancy outcomes. Hence, we summarize the immunological changes related to adverse reproductive outcomes in AIT and highlight the respective contributions of both humoral and cellular immune dysfunctions to pregnancy failures. Moreover, the direct impacts of AIT on maternal-fetal immune activation and biological influences to trophoblasts are discussed as well. All these associations require confirmation in larger studies, and the pathogenic mechanisms need to be better understood, which might provide useful information for clinical diagnosis and therapy of AIT.

Follicular GH and IGF1 Levels Are Associated With Oocyte Cohort Quality: A Pilot Study

INTRODUCTION

Oocyte quality contributes to the development of an optimal embryo and thus a successful pregnancy. The objective of this study was to analyse the association between oocyte cohort quality and the follicular levels of growth hormone (GH), insulin-like growth factor 1 (IGF1), 25-hydroxy vitamin D (25OHD), thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), free thyroxine (fT4) and antithyroid antibodies, as a function of intracytoplasmic sperm injection (ICSI) outcomes.

MATERIAL AND METHODS

We conducted a prospective comparative pilot study from January 2013 to December 2017. 59 ICSI cycles constituted an abnormal oocyte cohort (n=34 cycles, in which more than 50% of oocytes presented at least one morphological abnormality) and a normal oocyte cohort (n=25 cycles, in which 50% or less of the oocytes presented at least one morphological abnormality). GH, IGF1, 25OHD, TSH, fT3, fT4 and antithyroid antibodies were measured in follicular fluid.

RESULTS

The fertilisation rate was lower in the abnormal oocyte cohort (65.5% vs. 80%, respectively, p=0.012). Oocytes' proportion with at least one abnormality was 79.4% in the abnormal oocyte cohort and 29.0% in the normal oocyte cohort. The mean number of morphological abnormalities per oocyte was significantly higher in the abnormal oocyte cohort. The follicular levels of GH (4.98 vs. 2.75 mIU/L, respectively; p <0.01) and IGF1 (72.1 vs. 54.2 ng/mL, respectively; p=0.05) were higher in the normal oocyte cohort. There was no association with follicular levels of TSH, fT3, fT4, antithyroid antibodies, or 25OHD.

CONCLUSION

Oocyte cohort quality appears to be associated with follicular levels of GH and IGF1.

Impact of Thyroid Autoimmunity on In Vitro Fertilization/Intracytoplasmic Sperm Injection Outcomes and Fetal Weight

Several studies have reported the association between thyroid autoimmunity (TAI) and in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) outcomes. However, the findings remain controversial. We performed a large-scale retrospective cohort study to verify the effect of the presence of thyroid antibodies on IVF/ICSI outcomes and fetal growth and to evaluate the association between the types and titers of thyroid antibodies and adverse IVF/ICSI outcomes. A total of 16481 patients with infertility were referred to the Reproductive Center of Peking University Third Hospital for their first IVF/ICSI treatment between January 2018 and June 2019.Patients who sought IVF/ICSI treatment due to tubal or male factors infertility and who achieved fresh embryo transfer were included in our study. Finally, 778 patients with thyroid antibody positivity were selected as the TAI group, and 778 age-matched patients were included in the control group. The number of oocytes retrieved and high-graded embryos and the rates of clinical pregnancy, miscarriage, live birth, and preterm delivery were compared between the TAI and control groups. In addition, subgroup analysis was performed to demonstrate whether different types and titers of thyroid antibodies had different effects on IVF/ICSI outcomes. After adjusting for thyroid function, anti-Müllerian hormone levels, basal follicle stimulating hormone levels, basal estradiol levels and antral follicle count, the number of oocytes retrieved in the TAI group was significantly lower than that in the control group. No significant differences were observed between the two groups in the rates of clinical pregnancy, miscarriage, preterm delivery, live birth, and birth weight in singletons; however, the birth weight in twin pregnancy was significantly lower in the TAI group than in the control group. Subgroup analysis showed no association between the types or titers of thyroid antibodies and adverse IVF/ICSI outcomes. In conclusion, the presence of TAI in patients with infertility did not impair embryo quality or affect pregnancy outcomes, including clinical pregnancy, miscarriage, preterm delivery, and live birth. However, it decreased the number of oocytes retrieved and birth weight in twin pregnancy.

Thyroid autoimmunity and IVF/ICSI outcomes in euthyroid women: a systematic review and meta-analysis

BACKGROUND

Thyroid autoimmunity (TAI) - the presence of anti-thyroid peroxidase and/or anti-thyroglobulin antibodies - affects 8-14% of reproductively-aged women. It is hotly debated whether TAI adversely affects IVF/ICSI outcomes. This systematic review and meta-analysis evaluated the relationship between thyroid autoimmunity (TAI) and IVF/ICSI outcomes, both overall and amongst euthyroid women of known age using strict criteria for grouping pregnancy outcomes.

METHODS

The review was registered with PROSPERO: CRD42019120947. Searches were undertaken in MEDLINE, EMBASE, Web of Science and Cochrane Database from Inception-March 2020. Primary outcomes were clinical pregnancy rate, clinical miscarriage rate, biochemical pregnancy loss, livebirth rate per-cycle and live birth rate per clinical pregnancy (CP).

RESULTS

14 studies were included in the meta-analysis. Compared with women who tested negative for thyroid autoantibodies (TAI-), there was no significant difference in clinical pregnancy rate overall (OR 0.86; 95%CI [0.70, 1.05]; P = 0.14; 11 studies; I² = 29.0%), or in euthyroid women (OR 0.88; 95%CI [0.69, 1.12]; P = 0.29; 10 studies; I² = 32.0%). There was also no significant difference in clinical miscarriage rate overall (OR 1.04; 95%CI [0.52, 2.07]; P = 0.908; 8 studies; I² = 53%), or in euthyroid women (OR 1.18; 95%CI [0.52, 2.64]; P = 0.69; 7 studies; I² = 54%). There was no significant difference in biochemical pregnancy loss (OR 1.14; 95%CI [0.48, 2.72]; P = 0.769; 4 studies; I2 = 0.0%), live birth rate per cycle (OR 0.84; 95%CI [0.67, 1.06]; P = 0.145; I² = 1.7%), live birth rate per clinical pregnancy (OR 0.67; 95%CI [0.28, 1.60]; P = 0.369; I² = 69.2%), both overall and in euthyroid women as all studies included consisted of euthyroid women only. There was also no significant difference in number of embryos transferred, number of oocytes retrieved, mean maternal age or TSH levels overall or in euthyroid women.

CONCLUSION

The findings of the present study suggest that thyroid autoimmunity has no effect on pregnancy outcomes in euthyroid women alone, or in euthyroid women and women with subclinical hypothyroidism.

Does thyroid autoimmunity affect the reproductive outcome in women with thyroid autoimmunity undergoing assisted reproductive technology?

PROBLEM

Our study aims to investigate whether the anti-thyroperoxidase antibody (TPO-Ab) and TSH level in euthyroid women have any association with reproductive outcomes after the ART cycle.

METHODS OF STUDY

A total of 1107 patients who were enrolled in the study were divided into four groups based on serum TSH level and TPO-Ab status: group A, 0.3 ≤ TSH < 2.5 mIU/L and TPO-Ab^- ; group B, 0.3 ≤ TSH < 2.5 mIU/L and TPO-Ab⁺ ; group C, 2.5 ≤ TSH < 4.2 mIU/L, and TPO-Ab^- ; and group D, 2.5 ≤ TSH < 4.2 mIU/L, TPO-Ab⁺ . The differences in ART cycles and pregnancy outcomes were analyzed between study groups.

RESULTS

The fertilization rate in group D (73%) was significantly lower than that in groups A (83% P < .001), B (84% P = .001), and C (82% P = .002). The biochemical pregnancy rates of groups B (7%) and D (12%) were significantly higher than those of group A (2%) (P = .028 and P = .017, respectively). TPO-Ab was related to a higher biochemical pregnancy rate (P = .002, OR = 5.311, 95% CI 1.859-15.169) and TSH over 2.5 mIU/L was related to higher ICSI rate (P = .001, OR = 1.759, 95% CI 1.250-2.476) by logistic regression analysis. The receiver operating characteristic (ROC) also verified the results.

CONCLUSION

The impacts of TSH ≥ 2.5 mIU/L on the intracytoplasmic sperm injection (ICSI) rate, TSH ≥ 2.5 mIU/L and TPO-Ab⁺ on the fertilization rate, and TPO-Ab⁺ on the biochemical pregnancy rate, rather than the effect on abortion, clinical pregnancy, and live birth, were emphasized.

The influence of thyroid autoimmunity on pregnancy outcome in infertile women: a prospective study

Thyroid dysfunction and thyroid autoimmunity (TAI) have been reported to be linked to infertility, pregnancy loss and preterm birth. Infertile women undergoing assisted reproductive technology are recommended to maintain thyroid stimulating hormone (TSH) levels below 2.5 μIU/mL. It is unclear, however, whether levothyroxine (L-T4) treatment decreases the effects of TAI on fertility and pregnancy outcome in infertile women. We therefore aimed to clarify the influence of TAI on pregnancy undergoing L-T4 treatment for hypothyroidism. Prospectively recruited to this study were the 595 infertile women who visited the Utsunomiya Ladies Clinic between January 2013 and December 2015. Five patients with Graves' disease were excluded. Clinical profiles of 590 women were as follows: proportion of SCH = 19.6%, thyroid peroxidase antibody (TPOAb) positivity = 10.4%, and thyroglobulin antibody (TgAb) positivity = 15.1%. Fertility was not affected by any thyroid-associated factors. Regarding pregnancy outcomes, TPOAb titers were significantly higher in women who had miscarriage than in those progressed to delivery (46.4 ± 114.1 vs. 18.9 ± 54.6 IU/mL, p = 0.039), notably in those undergoing intrauterine insemination (p = 0.046) and in vitro fertilization (p = 0.023). Multivariate logistic regression analysis revealed that higher age (odds ratio 26.4, p < 0.001) and higher TPOAb titer (odds ratio 11.8, p = 0.043) were risk factors for miscarriage. Higher TPOAb titer should be considered as one of the risk factors for miscarriage in infertile women, even if they have been treated with L-T4 for hypothyroidism.