Impact of thyroid autoimmunity on cumulative delivery rates in in vitro fertilization/intracytoplasmic sperm injection patients

Impact of thyroid autoimmunity on the cumulative live birth rates after IVF/ICSI treatment cycles

BACKGROUND

Cumulative live birth rate (CLBR) is considered as the most important endpoint for assessing the probability of having a baby in a complete in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatment cycle. Many previous studies have focused on the association between thyroid autoimmunity (TAI) and live birth rate after first embryo transfer cycle, however, evidence on whether the presence of TAI affects the CLBR is lacking. The purpose of this study is to investigate the impact of TAI on the CLBR in a complete IVF/ICSI cycle.

METHODS

This retrospective study included 12,796 women who underwent their first IVF/ICSI treatment between January 2019 and February 2021. Based on the levels of thyroid antibodies, 2,603 women were assigned to the TAI group, and 10,193 women were assigned to the control group. Subgroup analysis was performed according to the different causes of infertility (including male factor only, ovulation disorder, tubal factor, endometriosis and unexplained infertility) and different types and titres of thyroid antibodies. The primary outcome in this study was CLBR, which included live births from the fresh embryo transfer cycle and all subsequent frozen-thawed embryo transfer cycles performed before December 2021.

RESULTS

There was no significant difference in the CLBR between the TAI and control groups, even after adjusting for relevant confounders including age, body mass index, cause of infertility, thyroid function, protocols of controlled ovarian stimulation, type of transfer (fresh vs. frozen), type of transferred embryo (cleavage-stage embryo vs. blastocyst), and fertilization method (IVF vs. ICSI) (cumulative live birth: 50.6% vs. 52.1%, OR 0.94, 95% CI 0.86-1.02, adjusted OR 0.97, 95%CI 0.89-1.06). Subgroup analysis showed that no significant difference was observed in CLBR between the TAI and control groups for all causes of infertility, except for infertility attributed to endometriosis. Among women with endometriosis, the CLBR was significantly lower in the TAI group than that in the control group; however, this difference was not significant after adjusting for potential confounders including age, body mass index, thyroid function, protocols of controlled ovarian stimulation, type of transfer (fresh vs. frozen), type of transferred embryo (cleavage-stage embryo vs. blastocyst), and fertilization method (IVF vs. ICSI) (cumulative live births: 43.1% vs. 51.0%, OR 0.73, 95% CI 0.53-0.99, adjusted OR 0.74, 95% CI 0.53-1.02). Another subgroup analysis demonstrated that the type and titre of thyroid antibody did not affect CLBR in women with TAI.

CONCLUSIONS

In our study, there was no significant difference in the CLBR between women with TAI and those without TAI, which suggests that TAI did not affect the chances of having a baby in a complete IVF/ICSI treatment cycle.

Impact of thyroid autoimmunity on pregnancy outcomes in euthyroid patients with recurrent implantation failure

RESEARCH QUESTION

Does thyroid autoimmunity (TAI) adversely affect pregnancy outcomes after IVF/intracytoplasmic sperm injection (ICSI) in euthyroid patients with recurrent implantation failure (RIF)?

DESIGN

This retrospective cohort study was conducted at the Reproductive Hospital Affiliated with Shandong University from November 2016 to September 2021. A total of 1031 euthyroid patients diagnosed with RIF were enrolled. Based on serum thyroid autoantibody concentrations, the participants were divided into two groups: the TAI-positive group (219 women with RIF) and the TAI-negative group (812 women with RIF). The parameters were compared between the two groups. Additionally, logistic regression was used to adjust related confounders for primary outcomes, and subgroup and stratified analyses were performed according to different thyroid autoantibody types and TSH concentrations.

RESULTS

There was no significant difference in ovarian reserve, ovarian response, embryo quality, pregnancy outcome or neonatal outcome between the two groups (P > 0.05). After adjustments for age, body mass index, thyroid-stimulating hormone and free thyroxine, the biochemical pregnancy rate in the TAI-positive group was significantly lower than that in the TAI-negative group (odds ratio 1.394, 95% CI 1.023-1.901, adjusted P = 0.036). Regarding the implantation rate, clinical pregnancy rate, pregnancy loss rate, stillbirth rate and live birth rate, no significant differences were observed even with subgroup and stratified analyses (P > 0.05).

CONCLUSIONS

TAI had no impact on pregnancy outcomes in euthyroid RIF patients who underwent IVF/ICSI. In clinical practice, interventions targeting thyroid autoantibodies in these patients should be implemented with caution and additional evidence is needed.

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.

High level of thyroid peroxidase antibodies as a detrimental risk of pregnancy outcomes in euthyroid women undergoing ART: A meta-analysis

Thyroid autoimmunity (TAI) triggered by genetic and epigenetic variation occurs mostly in women of reproductive age. TAI is described mainly by positivity of anti-thyroid peroxidase antibody (TPO-Ab) and/or thyroglobulin antibody (TG-Ab). TPO-Ab, but not TG-Ab, was suggested to be associated with pregnancy outcome in euthyroid women undergoing assisted reproductive technology (ART), but their results are conflicting. This meta-analysis was performed to decide whether the presence of TPO-Ab-in a concentration dependent manner-correlates with the success of ART. A systematic literature search was performed in the PubMed, Web of Science, and EMBASE databases for relevant articles published from January 1999 to April 2022, and these studies focused on the effect of TAI on pregnancy outcomes of women who underwent in vitro fertilization, intracytoplasmic sperm injection and intrauterine insemination and met the inclusion criteria: (i) the studies were prospective or retrospective study; (ii) all patients undergoing ART were tested for thyroid-related antibodies; (iii) the assessed ART outcomes included miscarriage rate (MR) or delivery rate (DR). The exclusion criteria were: (i) female congenital uterine malformation, chromosomal diseases and other infectious diseases; (ii) overt hypothyroidism or pre-existing thyroid disease; (iii) thrombus tendency. We divided the included patients into three groups according to the TPO-Ab threshold they defined: (i) TPO-Ab (-), threshold <34 IU/mL; (ii) TPO-Ab-34, threshold >34 IU/mL; (iii) TPO-Ab-100, threshold >100 IU/mL. We then extracted necessary relevant data, including MR and DR. Egger's test was used to evaluate the risk of publication bias. This meta-analysis included a total of 7 literatures involving 7466 patients with TAI (-) and 965 patients with TAI (+) and revealed that there was no significant difference between group TPO-Ab-34 and group TPO-Ab (-) in MR [risk ratio (RR): 0.61 (0.35, 1.08), p = 0.09] and DR [RR: 0.97 (0.83, 1.13), p = 0.69]. By contrast, compared to TPO-Ab (-) group, TPO-Ab-100 patients showed markedly higher MR [RR: 2.12 (1.52, 2.96), p = 0.0046], and lower DR [RR: 0.66 (0.49, 0.88), p < 0.0001] with high degree of statistical significance. This meta-analysis suggests that, for euthyroid patients, high level of TPO-Ab (>100 IU/mL) could adversely influence the pregnancy outcome of ART.

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.

The role of thyroid function in female and male infertility: a narrative review

PURPOSE

We herein aimed to review the new insights into the impact of impaired thyroid function on male and female fertility, spacing from spontaneous pregnancy to ART, with the objective of providing an updated narrative revision of the literature.

METHODS

This narrative review was performed for all available prospective, retrospective and review articles, published up to 2021 in PubMed. Data were extracted from the text and from the tables of the manuscript.

RESULTS

Thyroid dysfunction is frequently associated with female infertility, whereas its link with male infertility is debated. Female wise, impaired function is detrimental to obstetric and fetal outcomes both in spontaneous pregnancies and in those achieved thanks to assisted reproduction technologies (ART). Furthermore, the reference range of TSH in natural pregnancy and ART procedures has recently become a matter of debate following recent reports in this field. On the other hand, the impact of thyroid function on the male reproductive system is less clear, although a possible role is suggested via modulation of Sertoli and Leydig cells function and spermatogenesis.

CONCLUSION

Thyroid function should be carefully monitored in both male and female, in couples seeking spontaneous pregnancy as well as ART, as treatment is generally immediate and likely to improve chances of success.

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.

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 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.

The Efficacy of Assisted Reproduction in Women with a Wide Spectrum of Chronic Diseases - A Review

Assisted reproductive technology (ART) treatments in women with underlying chronic diseases have become increasingly frequent. The objective of this review is to provide an overview of the literature examining the chance of having a live born child after ART in women with chronic diseases, compared to other women receiving ART. We focused on some of the most prevalent chronic diseases in women during their reproductive years, ie ulcerative colitis, Crohn's disease, rheumatoid arthritis, multiple sclerosis, epilepsy, hyperthyroidism, hypothyroidism, and diabetes mellitus. Secondly, we studied the chance of successful implantation. The literature search was performed in the database Pubmed.gov. including all studies published before October 2020. Title and abstracts of 58 papers were reviewed, 37 papers were excluded and other 8 studies were excluded after full-text evaluation. Only 13 papers were eligible for review. Results indicate that women with ulcerative colitis, Crohn's disease, rheumatoid arthritis, hyperthyroidism, and diabetes mellitus type 2 might have problems with low implantation rate or early embryo development during ART. On the contrary, the few studies on women with hypothyroidism, diabetes mellitus type 1, and epilepsy suggest an equivalent chance of a live birth compared to other women undergoing ART. A possible explanation behind these differences could reside in the disease-specific dysregulation of the innate or adaptive immune system. To our knowledge, this is the first review on ART in women with chronic diseases, and it has disclosed that the evidence in this area is indeed sparse. We encourage others to examine live birth after ART in women with chronic diseases.

Immunological Risk Factors in Recurrent Pregnancy Loss: Guidelines Versus Current State of the Art

Around 1-5% of all couples experience recurrent pregnancy loss (RPL). Established risk factors include anatomical, genetic, endocrine, and hemostatic alterations. With around 50% of idiopathic cases, immunological risk factors are getting into the scientific focus, however international guidelines hardly take them into account. Within this review, the current state of immunological risk factors in RPL in international guidelines of the European Society of Reproduction and Embryology (ESHRE), American Society of Reproductive Medicine (ASRM), German/Austrian/Swiss Society of Obstetrics and Gynecology (DGGG/OEGGG/SGGG) and the Royal College of Obstetricians and Gynecologists (RCOG) are evaluated. Special attention was drawn to recommendations in the guidelines regarding diagnostic factors such as autoantibodies, natural killer cells, regulatory T cells, dendritic cells, plasma cells, and human leukocyte antigen system (HLA)-sharing as well as treatment options such as corticosteroids, intralipids, intravenous immunoglobulins, aspirin and heparin in RPL. Finally, the current state of the art focusing on both diagnostic and therapeutic options was summarized.

Impact of thyroid disease on fertility and assisted conception

Thyroid autoimmunity (TAI) and/or thyroid dysfunction are prevalent in women of reproductive age and have independently been associated with adverse fertility and pregnancy outcomes, in the case of spontaneous conception or after assisted reproductive technology (ART). Thus, it seems reasonable to screen for thyrotropin (TSH) and thyroid peroxidase autoantibodies (TPO-abs) in infertile women attempting pregnancy. However, even if the relationship between fertility and thyroid dysfunction and/or TAI persists when properly controlled for other variables, it remains challenging to claim causation. Several studies with different designs (cross sectional, case -control, prospective and retrospective cohort studies) have looked at the association between thyroid autoimmunity, thyroid function and fertility. Heterogeneity among study results are related to small numbers of included patients, poor study design, selection of causes of infertility and different assays used to measure TAI, thyroid hormones and TSH reference values. Indeed, there is no consensus regarding the upper limit of normal for TSH to define thyroid dysfunction and the cut-off levels for intervention. Furthermore, data from interventional trials looking at the impact of levothyroxine treatment on fertility outcome in randomised controlled studies are scarce. Despite the recent update of the guidelines by the American Thyroid Association (ATA) for the Diagnosis and Management of Thyroid Disease during Pregnancy and the postpartum, many questions remain unsettled in ART.

Risk factors of subclinical hypothyroidism and the potential contribution to miscarriage: A review

BACKGROUND

There is no clear cutoff value for thyroid-stimulating hormone (TSH) level that defines subclinical hypothyroidism (SCH). Moreover, TSH levels can be affected by numerous factors. Although mild SCH has been implicated in miscarriage, the relationship between TSH levels and miscarriage remains unelucidated.

METHODS

We reviewed nine known risk factors affecting TSH levels and 28 studies investigating the potential association between mild SCH and miscarriage, examining whether these factors were considered.

MAIN FINDINGS

Among 28 studies that examined whether mild SCH (TSH > 2.5 mIU/L) contributed to miscarriage, thyroid antibodies were measured in only 15. TSH measurement methods were described in 18 studies. Although the iodinated contrast medium used in hysterosalpingography (HSG) is stored in the body for a long time and is a risk factor for mild SCH, only one study described its potential impact on TSH levels. Nine studies, which concluded that mild SCH contributed to miscarriage, had thyroid status evaluated only after the onset of pregnancy, but not before.

CONCLUSION

TSH levels can be significantly affected by patient demographics and health history, country of origin, and fertility treatment. It is important to consider these factors while evaluating mild SCH. It remains unclear how mild SCH contributes to miscarriage.

Protein Expression Profile in IVF Follicular Fluid and Pregnancy Outcome Analysis in Euthyroid Women with Thyroid Autoimmunity

The objective of this study is to investigate the influence of the thyroid autoantibodies on the protein expression in follicular fluid and the clinical outcome of assisted reproductive technology. A total of 602 patients treated for infertility were screened; 49 euthyroid women who were positive for thyroid autoantibodies and 63 negative controls were recruited. Follicular fluid samples were analyzed using proteomics. Validation of target proteins in follicular fluid was performed by using parallel reaction monitoring. Differentially expressed proteins in follicular fluid, clinical pregnancy rate, abortion rate, and live-birth rate were analyzed. Clinical pregnancy rates and take-home baby rates in the thyroid autoimmunity (TAI) group were less than in the control group, but abortion rates in the TAI group were higher than in the control group (all P < 0.005). A total of 49 proteins were differentially expressed in the TAI-positive group. In Gene Ontology secondary annotations of all the proteins identified, five types of proteins were associated with the reproductive process. Among 11 proteins quantitatively identified by parallel reaction monitoring, angiotensinogen and fetuin-B were associated with reproduction. These differentially expressed proteins identified in this study involved multiple pathways according to the Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis. Our study provides evidence that some differentially expressed proteins between TAI-positive women and controls were associated with the reproductive process and closely related to important physiologic effects, which could partially explain the underlying mechanism link between TAI and the adverse outcomes of assisted reproductive technology.

The impact of thyroid autoantibodies on the cycle outcome and embryo quality in women undergoing intracytoplasmic sperm injection

Background

The influence of thyroid autoimmunity in in–vitro fertilization/intracytoplasmic sperm injection (ICSI) cycles is still a controversial issue. Although some women are euthyroid, some studies found thyroid dysfunction and thyroid autoimmunity increased the incidence of infertility. We aimed to evaluate the impact of anti-thyroid antibodies on the cycle parameters, embryo quality, and pregnancy outcomes in women who underwent ICSI cycles.

Results

Fertilization rate was significantly higher in anti-thyroid antibody-negative patients than in anti-thyroid antibody-positive patients (97.1 ± 10.5 vs. 91.5 ± 19.8, respectively, p = 0.003). Clinical pregnancy, miscarriage, and ongoing pregnancy rates were not different among study groups. The presence of top-quality embryo was lower in anti-thyroid antibody-positive patients but it did not reach any statistical significance (56.5% vs. 67.8%, p = 0.09). In the subgroup analysis, there were no significant differences except for the miscarriage rate according to the TSH threshold.

Conclusion

The clinical pregnancy and ongoing pregnancy were not affected by the positivity of anti-thyroid antibodies. We showed that thyroid autoimmunity may have an impact on fertilization rate and embryo quality in patients undergoing ICSI cycles. Miscarriage rate also increases with thyroid autoimmunity and TSH levels above 2.5 μIU/L.

The Impact of Preconception TSH on the Reproductive Outcomes of Infertile Women Undergoing the First Fresh D3 Embryo Transfer Cycle

PURPOSE

To investigate the association between high-normal preconception TSH levels and reproductive outcomes in infertile women undergoing the first fresh D3 embryo transfer.

METHODS

This was a retrospective study. Euthyroid patients undergoing the first fresh D3 embryo transfer from January 2018 to May 2019 were initially included. The patients were divided into a low-TSH (0.27-2.5 mIU/L) group and a high-normal TSH (2.5-4.2 Miu) group. The reproductive outcomes were compared between the groups.

RESULTS

A total of 1786 women were ultimately included, in which 1008 of whom had serum TSH levels between 0.27 and 2.5 mIU/L and 778 of whom had serum TSH levels between 2.5 and 4.2 mIU/L. The patients were highly homogeneous in terms of general characteristics. High-normal TSH levels had no adverse impact on the clinical pregnancy rate, miscarriage rate, or live birth rate (respectively, aOR = 0.92, 1.30, and 0.88 and P = 0.416, 0.163, and 0.219). No significant differences were observed in terms of gestational age, single live birth rates, and birth weight, or birth length.

CONCLUSION

High-normal TSH levels did not significantly influence reproductive outcomes in infertile women undergoing the first fresh D3 embryo transfer. Further studies are needed to test whether the results might be applicable to a wider population.

High-Normal Preconception TSH Levels Have No Adverse Effects on Reproductive Outcomes in Infertile Women Undergoing the First Single Fresh D5 Blastocyst Transfer

PURPOSE

To investigate the association between high-normal preconception TSH levels and reproductive outcomes in infertile women undergoing the first single fresh D5 blastocyst transfer.

METHODS

This was a retrospective study. Euthyroid patients undergoing the first single fresh D5 blastocyst transfer from January 2018 to May 2019 were initially included. The patients were divided into a low TSH (0.27-2.5 mIU/L) group and a high-normal TSH (2.5-4.2 mIU/L) group. The reproductive outcomes were compared between the groups.

RESULTS

A total of 824 women were ultimately included, 460 of whom had serum TSH levels less than 2.5 mIU/L and 364 of whom had serum TSH levels between 2.5 and 4.2 mIU/L. The patients were highly homogeneous in terms of general characteristics. High-normal TSH levels had no adverse impact on the clinical pregnancy rate, miscarriage rate, or live birth rate (respectively, aOR = 0.84, 0.65, 0.61, and P=0.234, 0.145, 0.083). No significant differences were observed in terms of gestational age, single live birth rates, birth weight, or birth length.

CONCLUSION

High-normal TSH levels did not significantly influence reproductive outcomes in infertile women undergoing the first single fresh D5 blastocyst transfer. Further studies are needed to test whether the results might be applicable to a wider population.

Thyroid Peroxidase Antibodies and Prospective Live Birth Rate: A Cohort Study of Women with Recurrent Pregnancy Loss

Background: Thyroid autoimmunity has been associated with pregnancy loss. Suggested mechanisms include thyroid function aberrations or an underlying breach of immunotolerance. We hypothesized that thyroid autoimmunity is a marker of the latter in women with recurrent pregnancy loss. This study investigated thyroid peroxidase antibody (TPOAb) status as a predictor of live birth in women with unexplained recurrent pregnancy loss. Methods: Cohort study of 825 consecutive women with recurrent pregnancy loss followed at the tertiary referral center for Recurrent Pregnancy Loss, Copenhagen University Hospital (Rigshospitalet), from 2011 to 2017. Recurrent pregnancy loss was defined as ≥3 consecutive losses, and as unexplained by absence of antiphospholipid syndrome, parental chromosome abnormality, or uterus malformation. Upon first visit, all women were screened for thyrotropin (TSH) and TPOAbs (TPOAb positivity: ≥60 kIU/L). Adjusted logistic regression analyses included as covariates the following: maternal age, TSH, previous number of losses, body mass index, smoking, pregnancy achieved by assisted reproductive technology, and thyroxine replacement (T4) treatment. Results: We included 825 women with a total of 3246 previous losses, of whom 139 (16.8%) were TPOAb positive. TPOAb positivity was not associated with the previous number of losses (p = 0.41). Women with unexplained recurrent pregnancy loss had a live birth rate in the first pregnancy after referral of 62.8% (285 of 454). TPOAb positivity was found in 78 of 454 (17.2%) women and was associated with a reduced live birth rate (51.3% vs. 65.2%, p = 0.02, adjusted odds ratio [aOR] 0.2 [0.1-0.6] p = 0.001). Treatment with T4 increased live birth rate significantly (aOR 3.7 [1.4-9.8], p = 0.007), and TPOAb-positive women receiving T4 had a live birth rate similar to that of TPOAb-negative women not receiving T4 (p = 0.70). Only 30% of TPOAb-positive women and 39% of women treated with T4 during pregnancy had known thyroid disease at referral. Conclusion: In a large cohort of women with unexplained recurrent pregnancy loss, TPOAb positivity was predictive of a reduced live birth rate. However, T4 treatment improved odds of live birth. The study supports screening for TPOAbs as a risk factor in women with unexplained recurrent pregnancy loss. The beneficial effect of T4 treatment in this high-risk group needs confirmation by randomized controlled trials. Close collaboration between fertility experts and endocrinologists is paramount.

The Impact of Autoantibodies on IVF Treatment and Outcome: A Systematic Review

The role of autoantibodies in in vitro fertilization (IVF) has been discussed for almost three decades. Nonetheless, studies are still scarce and widely controversial. The aim of this study is to provide a comprehensive systematic review on the possible complications associated to autoantibodies (AA) impeding the chances of a successful IVF cycle. An Embase, PubMed/Medline and Cochrane Central Database search was performed on 1 December 2018, from 2006 until that date. From the 598 articles yielded in the search only 44 relevant articles ultimately fulfilled the inclusion criteria and were qualitatively analyzed. Five subsets of results were identified, namely, thyroid related AA, anti-phospholipid antibodies, anti-nuclear antibodies, AA affecting the reproductive system and AA related to celiac disease. It may be implied that the majority of auto-antibodies exert a statistically significant effect on miscarriage rates, whereas the effects on clinical pregnancy and live birth rates differ according to the type of auto-antibodies. While significant research is performed in the field, the quality of evidence provided is still low. The conduction of well-designed prospective cohort studies is an absolute necessity in order to define the impact of the different types of autoantibodies on IVF outcome.

Levothyroxine supplementation on assisted reproduction technology (ART) outcomes in women with subtle hypothyroidism: a retrospective study

The need for treating subclinical hypothyroidism (SCH) in women undergoing assisted reproduction technology (ART) is under debate. Moreover, it is known that controlled ovarian hyperstimulation (COH) protocols may impair the thyroidal axis. Therefore, we evaluated if levothyroxine (L-T4) supplementation in SCH women before undergoing ART positively affects the main reproductive outcomes. We retrospectively analyzed in vitro fertilization (IVF) data of 4147 women submitted to 6545 cycles in a tertiary care IVF Center (January 2009-December 2014). L-T4 (1.4-2.0 mcg/kg) treatment was offered to all women with a pre-cycle TSH >2.5 mIU/L before starting COH and main ART outcomes were compared in euthyroid and L-T4-treated women undergoing ART. Among 4147 women, 1074 (26%) were affected by SCH and were treated with L-T4 before COH was started. No statistically significant differences among L-T4-treated and euthyroid women group were observed regarding pregnancy rate, respectively, per cycle (27.67% vs 26.37%; p = .314) and per embryo transfer (30.13% vs 29.17%; p = .489), live birth rate, respectively, per cycle (21.58% vs 20.38%; p = .304) and per embryo transfer (23.49 vs 22.54%; p = .449) and the rest of primary and secondary efficacy endpoints. Early L-T4 treatment for infertile women with a subtle thyroid dysfunction may mitigate and protect from the negative effects of SCH in the setting of ART, and may preventively overcome also the negative impact of COH on thyroidal axis.

'Does levothyroxine improve pregnancy outcomes in euthyroid women with thyroid autoimmunity undergoing assisted reproductive technology?'

Evidence on the treatment of euthyroid infertile women and thyroid autoimmunity with thyroid hormone is scare, and therefore the recent study by Wang et al. is a welcome addition to it. Based on their results, thyroid hormone seems not to be indicated to decrease the miscarriage rate in that particular group of infertile women. This comment is meant to put the study results into perspective with the available evidence and the current guidelines, and to highlight its strengths and weaknesses.

Thyroid autoimmunity and intracytoplasmic sperm injection outcome: a systematic review and meta-analysis

BACKGROUND

Since 2010, three meta-analyses have been published on the impact of thyroid autoimmunity (TAI) on pregnancy outcomes in infertile women treated with assisted reproductive technology (ART). The initially observed high risk of miscarriage became very low in the most recent meta-analysis published in 2016.

OBJECTIVE

To investigate whether the lower risk of miscarriage in the latest meta-analysis was associated with the increased use of intracytoplasmic sperm injection (ICSI) in recent studies.

DATA SOURCE

MEDLINE was searched from January, 1990, to May, 2017.

STUDY SELECTION

Data from case-control and cohort studies, on ART (IVF/ICSI) pregnancy outcomes in women with and without TAI. Only studies were included in which women were treated with ICSI.

DATA EXTRACTION AND SYNTHESIS

Four studies were retained including 1855 ICSI cycles (290 with and 1565 without TAI). In women with a clinical pregnancy (114 ICSI cycles with TAI and 651 without), there was no difference in miscarriage or live birth rates: respective combined OR 0.95 (95% CI, 0.48 to 1.87) and 1.12 (95% CI, 0.62 to 2.03). There was no difference in age in women with and without TAI: combined mean difference of 0.13 years (95% CI, -0.51 to 0.76), but serum TSH was higher in women with TAI: combined mean difference of 0.20 mIU/L (95% CI, 0.07 to 0.33).

CONCLUSION

Infertile women with TAI treated with ICSI had no increased risk of a first trimester miscarriage compared with women without TAI.

Preconceptional antithyroid peroxidase antibodies, but not thyroid-stimulating hormone, are associated with decreased live birth rates in infertile women

OBJECTIVE

To study whether preconceptual thyroid-stimulating hormone (TSH) and antithyroid peroxidase (TPO) antibodies are associated with poor reproductive outcomes in infertile women.

DESIGN

Secondary analysis of data from two multicenter, randomized, controlled trials conducted by the Reproductive Medicine Network of the Eunice Kennedy Shriver National Institute of Child Health and Human Development. Multivariable logistic regression analyses were performed to assess the association between preconceptual TSH levels and anti-TPO antibodies.

SETTING

Not applicable.

PATIENT(S)

Serum samples from 1,468 infertile women were utilized.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Cumulative conception, clinical pregnancy, miscarriage, and live birth rates were calculated.

RESULT(S)

Conception, clinical pregnancy, miscarriage, and live birth rates did not differ between patients with TSH ≥2.5 mIU/L vs. TSH < 2.5 mIU/L. Women with anti-TPO antibodies had similar conception rates (33.3% vs. 36.3%) but higher miscarriage rates (43.9% vs. 25.3%) and lower live birth rates (17.1% vs. 25.4%) than those without anti-TPO antibodies. Adjusted, multivariable logistic regression models confirmed elevated odds of miscarriage (odds ratio 2.17, 95% confidence interval 1.12-4.22) and lower odds of live birth (oddr ratio 0.58, 95% confidence interval 0.35-0.96) in patients with anti-TPO antibodies.

CONCLUSION(S)

In infertile women, preconceptional TSH ≥2.5 mIU/L is not associated with adverse reproductive outcomes; however, anti-TPO antibodies are associated with increased risk of miscarriage and decreased probability of live birth.

CLINICAL TRIAL REGISTRATION NUMBER

PPCOS II NCT00719186; AMIGOS NCT01044862.

Increased levels of CCR7(lo)PD-1(hi) CXCR5+ CD4+ T cells, and associated factors Bcl-6, CXCR5, IL-21 and IL-6 contribute to repeated implantation failure

In vitro fertilization-embryo transfer (IVF-ET) can be used by infertile couples to assist with reproduction; however, failure of the embryo to implant into the endometrial lining results in failure of the IVF treatment. The present study investigated the expression of chemokine receptor 7 (CCR7)(lo) programmed death-1(PD-1)(hi) chemokine receptor type 5 (CXCR5)⁺ cluster of differentiation 4 (CD4)⁺ T cells and associated factors in patients with repeated implantation failure (RIF). A total of 30 females with RIF and 30 healthy females were enrolled in the current study. Flow cytometry was used to detect the proportion of CCR7(lo)PD-1(hi) CXCR5⁺ CD4⁺ T cells in the peripheral blood. Cytokine bead arrays were performed to detect the levels of interleukin (IL)-6, −4 and −2 in the serum. ELISAs were used to detect the level of IL-21 in the serum. Quantitative real time polymerase chain reaction analysis and immunohistochemistry were used to investigate the expression of B-cell lymphoma 6 (Bcl-6), chemokine receptor type 5 (CXCR5) and IL-21 in the endometrium. The results revealed that the percentage of CCR7(lo)PD-1(hi) CXCR5⁺ CD4⁺ T cells was increased in the RIF group compared with the control group during the mid luteal phase. The mRNA and protein levels of Bcl-6, IL-21 and CXCR5 in the endometrium and the concentrations of IL-21 and IL-6 in the serum were significantly increased in the RIF group; however, no significant difference was observed between the two groups in regards to the expression of IL-4 and IL-2. Furthermore, a significant positive correlation was identified between the percentage of CCR7(lo)PD-1(hi) CXCR5⁺ CD4⁺ T cells and IL-21 and IL-6 levels. The expression of IL-21 also had a positive correlation with Bcl-6 and CXCR5 expression in the RIF group. These results suggest that increased levels of CCR7(lo)PD-1(hi) CXCR5⁺ CD4⁺ T cells and associated factors contribute to RIF and could therefore be a potential therapeutic target.

A post-publication analysis of the idealized upper reference value of 2.5 mIU/L for TSH: Time to support the thyroid axis with magnesium and iron especially in the setting of reproduction medicine

Laboratory medicine approaches the evaluation of thyroid function mostly through the single determination of the blood level of thyroid stimulating hormone (TSH). Some authors have suggested an upper reference value for TSH of 2.5 mIU/L. This suggestion has not been confirmed by recent clinical studies. These studies have delivered a clinically valid reference range going from 0.3 to 3.5 mIU/L. These values are valid for both for the general population as well as in the setting of fertility and pregnancy. Current biochemical evidence about the elements required to maintain thyroid function shows that these not only include dietary iodine but also magnesium, iron, selenium and coenzyme Q10. Iron is important for the synthesis of thyroid peroxidase; magnesium-ATP contributes to the active process of iodine uptake; iodine has to be sufficiently present in the diet; selenium acts through selenoproteins to protect the thyroid cell during hormone synthesis and in deiodination of thyroxine; coenzyme Q10 influences thyroid vascularity. As a consequence, good clinical practice requires additional biochemical information on the blood levels of magnesium, selenium, coenzyme Q10 as well as iron status. Since these elements are also important for the maintenance of reproductive function, we postulate that they constitute the connecting link between both endocrine systems.