TPO antibody positivity and adverse pregnancy outcomes

Research progress in the construction of animal models of autoimmune thyroiditis

Autoimmune thyroiditis (AIT), also known as Hashimoto's thyroiditis (HT), is an autoimmune disease that is characterised by elevated thyroid-specific antibody titres. The incidence of AIT is increasing year over year, making it urgent to establish a suitable animal model for this condition, in order to better explore its pathogenesis and potential pharmaceutical mechanisms for treatment. Owing to a lack of basic research on this disease, problems such as disparate modelling methods with unclear and varying success rates make it difficult for researchers to obtain effective information on AIT in the short term. This report summarises and analyzes the current literature on AIT and combines actual operability to explain the selection and specific implementation processes behind the uses of different modelling approaches, to provide a better overall understanding of autoimmune thyroid diseases.

Parental autoimmunity and offspring risks of rheumatic diseases: a nationwide population-based study

OBJECTIVE

Familial aggregation of systemic autoimmune diseases is frequently reported, but little is known about how fathers and mothers differentially contribute to the development of autoimmune diseases in their offspring. This study aimed to investigate the impact of maternal and paternal autoimmunity on the risk of offspring rheumatic diseases.

METHODS

We constructed a nationwide population-based cohort using data from the Maternal and Child Health Database and the Taiwan National Health Insurance Research Data (NHIRD) from 2004 to 2019. The outcome was presence of an autoimmune disease in the offspring. Inverse probability of treatment-weighted Cox models were used to estimate adjusted hazard ratios (aHRs) and 95% CIs for autoimmune diseases.

RESULTS

Babies born to a father or mother with an autoimmune disease had, respectively, 1.22 times and 1.38 times the risk of developing an autoimmune disease compared with their counterparts with no parental autoimmune diseases. Maternal autoimmunity substantially contributed to the risk of SLE (aHR = 5.46, 95% CI: 5.28-5.66), and paternal autoimmunity contributed to the risk of JIA (aHR = 1.76, 95% CI: 1.71-1.81) and of type 1 diabetes mellitus (aHR = 1.59, 95% CI: 1.39-1.81) in their offspring. The contributions of mothers to the risk of development of SLE (aHR = 8.55, 95% CI: 8.10-9.02) and inflammatory myopathy (aHR = 2.08, 95% CI: 1.72-2.51) in their offspring were exacerbated in boys. Babies of two parents with an autoimmune disease showed a 1.39-fold risk of developing an autoimmune disease. The maternal contribution effect was stronger for preterm births than for full-term births.

CONCLUSION

This study demonstrated broadly how autoimmune diseases pass from parents to infants of both genders and separately quantified the maternal and paternal contributions to disease.

The Impacts of Inflammatory and Autoimmune Conditions on the Endometrium and Reproductive Outcomes

Background: A healthy pregnancy begins with an adequate endometrial state, even before the arrival of a blastocyst. Proper endometrial priming and the development of a tolerogenic decidua are key steps in creating the perfect environment for implantation and pregnancy. In these processes, the involvement of the maternal immune system seems to be of great relevance, modulating the different decidual immune populations to prepare the endometrium for a potential pregnancy. However, certain local pathologies of an inflammatory and autoimmune nature appear to have a direct impact on these phenomena, thus altering patients' reproductive outcomes. Methods: This literature review analyzes original articles, reviews, systematic reviews, and meta-analyses published between 1990 and 2024, concerning the impact of different inflammatory and autoimmune conditions on endometrial status and fertility. The included papers were obtained from Medline (Pubmed) and the Cochrane library. Results: There is evidence that endometriosis, adenomyosis, and chronic endometritis, through the promotion of a chronic inflammatory environment, are capable of altering endometrial immune populations, and, thus, processes essential for early pregnancy. Among other effects, these conditions have been linked to impaired decidualization, alterations in progesterone responsiveness, and hindered placentation. Similarly, antiphospholipid syndrome (APS), thyroid dysfunction, diabetes, and other pathologies related to glucose and gluten metabolism, due to their autoimmune nature, also appear to have a local impact on the uterine environment, affecting reproductive success through different mechanisms, including altered hormonal response and, again, impaired decidualization. Conclusions: The management of inflammatory and autoimmune diseases in assisted reproduction patients is gaining importance due to their direct impact on the endometrium. It is necessary to follow current expert recommendations and established therapeutic approaches in order to improve patients' prospects, ranging from antibiotic treatment in chronic endometritis to heparin and aspirin in APS, as well as hormonal treatments for endometriosis/adenomyosis or a gluten-free diet in celiac disease. All of them and the rest of the therapeutic perspectives, both current and under investigation, are presented throughout this work, assessing the possible improvements for reproductive outcomes.

A predictive model of pregnancy loss using pre-pregnancy endocrine and immunological parameters in women with abnormal glucose/lipid metabolism and previous pregnancy loss

OBJECTIVE

To investigate the clinical and endocrine risk factors for pregnancy loss in women with abnormal glucose/lipid metabolism and a history of pregnancy loss, and to develop a predictive model to assess the risk of pregnancy loss in these women's subsequent pregnancies.

METHODS

Patients with a history of pregnancy loss who had abnormal glucose/lipid metabolism were retrospectively included in this study, and their pre-pregnancy baseline and clinical characteristics were collected. A predictive nomogram was constructed based on the results of the multivariable logistic regression model analysis, and its calibration and discriminatory capabilities were evaluated. The internal validation was then performed and the net benefits were assessed by the clinical decision curve.

RESULTS

The predictive model was eventually incorporated eight variables, including maternal age, previous pregnancy losses, anticardiolipin antibody (aCL) IgG, aCL IgM, thyroid peroxidase antibody, complement 4, free thyroxine and total cholesterol. The area under the curve (AUC) of the nomogram was 0.709, and Chi-square value and P value of the Hosmer-Lemeshow test were 12.786 and 0.119, respectively, indicating that the nomogram had a satisfactory calibration and discriminatory performance. The validation cohort showed a similar result for the discrimination of the nomogram (AUC = 0.715). The clinical decision curve demonstrated the nomogram had good positive net benefits.

CONCLUSIONS

This is the first study to predict the risks of subsequent pregnancy loss in women with abnormal glucose/lipid metabolism and history of pregnancy loss using pre-pregnancy clinical and endocrine parameters. This predictive nomogram may provide clinicians assistance to personalize the management of subsequent pregnancies in these patients.

[Humoral Immunity Abnormalities in Advanced Maternal-Age Women With Recurrent Spontaneous Abortion: A Single Center Study]

Objective

To determine the humoral immunity in advanced maternal-age women with recurrent spontaneous abortion (RSA).

Methods

A retrospective study was performed between January 2022 and October 2023 in the Department of Reproductive Immunity of Shanghai First Maternity and Infant Hospital. Women with RSA were recruited and multiple autoantibodies were tested. Multivariate logistic regression was performed to compare the associations between different age groups (20 to 34 years old in the low maternal-age group and 35 to 45 years in the advanced maternal-age group) and multiple autoantibodies, while controlling for three confounding factors, including body mass index (BMI), previous history of live birth, and the number of spontaneous abortions. Then, we investigated the differences in the humoral immunity of advanced maternal-age RSA women and low maternal-age RSA women.

Result

A total of 4009 women with RSA were covered in the study. Among them, 1158 women were in the advanced maternal-age group and 2851 women were in the low maternal-age group. The prevalence of antiphospholipid syndrome, systemic lupus erythematosus, Sjogren's syndrome, rheumatoid arthritis, and undifferentiated connective tissue disease was 15.6% and 14.1%, 0.0% and 0.1%, 0.9% and 0.9%, 0.3% and 0.0%, and 23.7% and 22.6% in the advanced maternal-age group and low maternal-age group, respectively, showing no statistical difference between the two groups. The positive rates of antiphospholipid antibodies (aPLs), antinuclear antibody (ANA), extractable nuclear antigen (ENA) antibody, anti-double stranded DNA (dsDNA) antibody, anti single-stranded DNA (ssDAN) antibody, antibodies against alpha-fodrin (AAA), and thyroid autoimmunity (TAI) were 19.1% and 19.5%, 6.6% and 6.6%, 9.2% and 10.5%, 2.0% and 2.0%, 2.2% and 1.2%, 5.1% and 4.9%, and 17.8% and 16.8%, respectively. No differences were observed between the two groups. 1.6% of the women in the advanced maternal-age group tested positive for lupus anticoagulant (LA), while 2.7% of the women in the low maternal-age group were LA positive, with the differences being statistically significant (odds ratio=0.36, 95% confidence interval: 0.17-0.78). In the 4008 RSA patients, the cumulative cases tested positive for the three antibodies of the aPLs spectrum were 778, of which 520 cases were positive for anti-β2 glycoprotein Ⅰ antibodies (β2GPⅠ Ab)-IgG/IgM, 58 were positive for aCL-IgG/IgM, 73 were positive for LA, 105 were positive for both β2GPⅠ Ab-IgG/IgM and aCL-IgG/IgM, 17 were positive for both β2GPⅠ Ab-IgG/IgM and LA, 2 were positive for both aCL-IgG/IgM and LA, and 3 were positive for all three antibodies.

Conclusion

Our study did not find a difference in humoral immunity between RSA women of advanced maternal age and those of low maternal age.

Coexistence of Endometriosis and Thyroid Autoimmunity in Infertile Women: Impact on in vitro Fertilization and Reproductive Outcomes

OBJECTIVES

The objective of the study was to evaluate the prevalence and impact of impaired thyroid-stimulating hormone (TSH) levels on the reproductive outcomes of in vitro fertilization patients diagnosed with endometriosis and compared to controls without endometriosis.

DESIGN

This is a retrospective cohort study on prospectively collected data.

SETTING

The study was conducted at tertiary care university hospital.

PARTICIPANTS

Participants were infertile women with histopathological diagnosis of endometriosis.

METHODS

For 12 months (January 2018 to January 2019), women were deemed suitable and subsequently divided according to serum TSH levels above or below 2.5 mIU/L and compared to patients without endometriosis. Needed sample size was at least 41 patients for each cohort of women. Co-primary outcomes were the live birth rate (LBR), clinical pregnancy rate (CPR), and pregnancy loss rate (PLR).

RESULTS

Overall, 226 women (45 with endometriosis and 181 controls without endometriosis) were included. Diagnoses of Hashimoto thyroiditis were significantly more frequent in women with rather than without endometriosis (14/45 [31.1%] vs. 27/181 [14.9%]; p = 0.012). Similarly, in women with endometriosis, Hashimoto diagnosis rates were higher with TSH ≥2.5 mIU/L compared to TSH <2.5 mIU/L (9/15 [60%] vs.5/30 [16.6%]; p = 0.001) so were the Hashimoto diagnosis rates in control group (women without endometriosis) with TSH ≥2.5 mIU/L compared to TSH <2.5 mIU/L (17/48 [35.4%] vs. 10/133 [7.5%], respectively; p = 0.001). Effect size analysis confirmed an increased risk of Hashimoto thyroiditis in women with endometriosis and TSH ≥2.5 mIU/L compared to women with endometriosis and TSH <2.5 mIU/L (risk ratio [RR] 3.60 [95% CI 1.46-8.86]) and in women with endometriosis and TSH ≥2.5 mIU/L compared to non-endometriotic euthyroid patients (RR 7.98 [95% CI 3.86-16.48]). Dysmenorrhea risk was higher in endometriotic euthyroid women compared to euthyroid patients with no endometriosis (RR 1.87 [95% CI 1.21-2.87]). The risk was still increased in euthyroid women with endometriosis relative to dysthyroid women with no endometriosis (RR 1.97 [95% CI 1.11-3.50]). There were no significant differences between the four groups for CPR, LBR, PLR and retrieved oocytes, immature oocytes, degenerated and unfertilized oocytes, cultured blastocysts, embryos and transferred embryos.

LIMITATIONS

Limitations of the study were retrospective design, limited sample size, and use of different ovarian stimulation protocol.

CONCLUSIONS

Thyroid autoimmunity seems more common in women with endometriosis and TSH over 2.5 mIU/L. However, there was no significant impact on in vitro fertilization and reproductive outcomes related to the coexistence of endometriosis, Hashimoto disease, and higher TSH levels. Due to limitations of the study, additional evidence is required to validate the abovementioned findings.

The relationship between thyroid peroxidase antibody and differentiated thyroid cancer: a systematic review and meta-analysis

Background

Thyroglobulin antibody (TgAb) has been found to be associated with the occurrence and development of differentiated thyroid cancer (DTC) for several years, but there is still controversy over whether thyroid peroxidase antibody (TPOAb) is related to differentiated thyroid cancer.

Methods

We scrutinized relevant studies published up to July 2023 across four major databases including PubMed, Embase, Cochrane Library, and Web of Science, to examine the association between TPOAb and DTC. Clinical outcome measures include the incidence of DTC, tumor size, extrathyroidal invasion, lymph node metastasis, multifocality, recurrence and bilaterality.

Results

12 original studies were included, involving a total of 20,330 subjects. Our analysis of the included studies revealed that TPOAb+ individuals exhibited a higher risk of developing DTC (OR=1.57 [95% CI: 1.00-2.45], p=0.049) than TPOAb- individuals. Furthermore, TPOAb+ DTC patients were more prone to present with bilateral (OR=1.40 [95% CI: 1.21-1.62], p<0.00001) and multifocal (OR=1.40 [95% CI: 1.23-1.60], p<0.00001) tumors than TPOAb- patients. Sensitivity analysis indicated a high sensitivity for these three findings. No significant differences in the risk of extrathyroidal extension and lymph node metastasis, recurrence rate, tumor size, were observed between TPOAb+ and TPOAb- DTC patients.

Conclusion

The presence of TPOAb is correlated with an increase prevalence of DTC. However, its effectiveness as a prognostic marker for DTC patients warrants further investigation.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023448824.

The effects of metabolic indicators and immune biomarkers on pregnancy outcomes in women with recurrent spontaneous abortion: a retrospective study

Background

The etiology of recurrent spontaneous abortion (RSA) remains elusive despite specific investigations affirming the association between RSA and thyroid autoimmunity (TAI). This study explores the immunological and metabolic profiles of RSA patients exhibiting positive thyroid antibodies and their connection with the rates of first-trimester miscarriage and live births. The aim is to provide further guidance for clinical interventions.

Methods

A retrospective analysis included 478 women with RSA. Thyroid profile, thyroid peroxidase antibodies, and anti-thyroglobulin antibodies were measured in all participants. The clinical characteristics and pregnancy outcomes of RSA women were compared between thyroid autoimmunity (TAI)-positive and TAI-negative patients. Significant factors associated with adverse pregnancy outcomes and risk prediction models were explored in TAI-positive patients. Correlation analysis was used to identify specific metabolic or immune biomarkers associated with thyroid autoantibodies.

Results

The prevalence of TAI was 18.6%. Compared with women without TAI, the thyroid-stimulating hormone (TSH) concentration of TAI-positive RSA was significantly higher (2.80 ± 2.98 vs 1.89 ± 1.17, p=0.006). After 28 weeks, the live birth rate of the TAI-positive group was lower than that of the TAI-negative group, with statistical significance (p<0.05). The immune biomarkers that differed between RSA women with live births and those with first-trimester miscarriages were complement C4 and interleukin-6, respectively, in TAI-negative and TAI-positive women. Then, a risk prediction model for first-trimester miscarriage was constructed for TAI-positive women with an AUC of 0.81. Finally, some factors related to thyroid peroxidase antibody (TPO-Ab) levels were explored, and it was found that TPO-Ab levels were positively correlated with free thyroxine and negatively correlated with 25 hydroxyvitamin D, interleukin-4, and fasting blood glucose in RSA patients.

Conclusion

TAI-positive RSA patients have higher first-trimester miscarriage rates and a lower live birth rate, which may be related to metabolic immune shifts in TAI-positive RSA patients.

Efficacy and safety of Ophiocordyceps sinensis in the treatment of Hashimoto's thyroiditis: a systematic review and meta-analysis

Objective: To evaluate the efficacy and safety of Ophiocordyceps sinensis (OS) preparations for the treatment of Hashimoto's thyroiditis (HT). Methods: We searched eight databases to collect randomized controlled trials (RCTs) of OS combined with a low-iodine diet or levothyroxine for HT. The search period was from inception to June 2023. Meta-analysis was performed using Revman 5.3 software after two evaluators independently screened the literature, extracted data, and evaluated the risk of bias of the included studies. The GRADE system was used to assess the certainty of evidence. Results: A total of 14 RCTs involving 1,014 patients with HT were included. Meta-analysis showed that OS preparations combined with a low-iodine diet were more effective in reducing thyroid peroxidase antibody (TPOAb) [SMD = -3.81, 95% CI (-5.07, -2.54), p < 0.00001] and thyroglobulin antibody (TgAb) [SMD = -4.73, 95% CI (-6.86, -2.61), p < 0.00001] compared to a low-iodine diet. Compared with levothyroxine treatment alone, OS preparations combined with levothyroxine further reduced TPOAb [SMD = -2.04, 95% CI (-2.82, -1.26), p < 0.00001], TgAb [SMD = -2.01, 95% CI (-2.68, -1.33), p < 0.00001], tumor necrosis factor alpha (TNF-α) [SMD = -3.40, 95% CI (-5.66, -1.14), p = 0.003], interleukin-2 (IL-2) [SMD = -2.31, 95% CI (-3.98, -0.65), p = 0.006], and interleukin-6 (IL-6) [MD = -4.16, 95% CI (-6.17, -2.15), p < 0.0001], and elevated free thyroxine (FT4) [SMD = 1.34, 95% CI (0.59, 2.08), p = 0.0004], but no significant effect on free triiodothyronine (FT3) [SMD = 0.83, 95% CI (-0.12, 1.78), p = 0.09] and thyroid stimulating hormone (TSH) [SMD = -0.80, 95% CI (-1.71, 0.11), p = 0.08]. In terms of safety, three studies reported adverse reactions in 10 patients in each of the experimental and control groups. Conclusion: OS preparations in combination with other treatments (low-iodine diet or levothyroxine) may decrease thyroid autoantibodies and inflammatory responses in patients with HT. In HT patients with hypothyroidism, the combination of the OS preparations with levothyroxine also improved FT4. However, the quality of the included studies was generally low. Moreover, the safety of OS preparations remains unclear. Therefore, more high-quality, multicenter, large-sample RCTs are needed in the future to validate the efficacy and safety of OS preparations. Systematic Review Registration: https://www.crd.york.ac.uk/prospero, identifier CRD42023432663.

Th1 or Th2 cytokines are correlated with Tregs and T cell subsets and pregnancy outcomes in patients with autoimmune thyroid disease during early, middle, late pregnancy, and postpartum period

Autoimmune thyroid disease (AITD) is a T lymphocytes-mediated autoimmune disorder affecting pregnant women. The current study sought to determine the correlations between T helper-1 (Th1)/T helper-2 (Th2) cytokines and regulatory T cells (Tregs) and T cell subsets and pregnancy outcomes in AITD patients during early pregnancy (T1), middle pregnancy (T2), late pregnancy (T3), and postpartum period (PP). A total of 60 patients with Graves' disease, 60 patients with Hashimoto's thyroiditis, and 30 healthy pregnant women were initially enrolled in the study. Thyroid hormones and antibodies, Th1 or Th2 cytokines, transforming growth factor-β, Tregs, CD4+ T helper cells (CD4+), CD8+ T helper cells (CD8+) levels were determined by means of Maglumi2000 automatic chemiluminescence instrument, enzyme-linked immunosorbent assay, and flow cytometry. Our findings demonstrated higher IFN-γ and IL-2 levels, along with lower IL-4, IL-10, TGF-β, Treg, and CD4+/CD8+ levels in AITD patients during T1, T2, T3, and PP. Furthermore, the TGF-β, Treg, and CD4+/CD8+ levels were lower in the IFN-γ/IL-2 high expression group but higher in the IL-4/IL-10 high expression group. The IFN-γ and IL-2 levels were higher, while IL-4 and IL-10 level were lower in AITD patients with adverse pregnancy outcomes. Lastly, Th1 cytokines were higher and Th2 cytokines were lower in AITD patients and elicited correlation with Tregs and CD4+/CD8+ levels. Collectively, our findings highlighted that up-regulation of Th1 cytokines may increase the percentage of adverse pregnancy outcomes in AITD patients.

Association of maternal thyroid peroxidase antibody during pregnancy with placental morphology and inflammatory and oxidative stress responses

Background

Studies suggest that thyroid peroxidase antibody (TPOAb) positivity exposure during pregnancy may contribute to changes in placental morphology and pathophysiology. However, little is known about the association of maternal TPOAb during pregnancy with placental morphology and cytokines. This study focuses on the effect of repeated measurements of maternal TPOAb during pregnancy on the placental morphology and cytokines.

Methods

Based on Ma'anshan Birth Cohort (MABC) in China, maternal TPOAb levels were retrospectively detected in the first, second and third trimesters. Placental tissues were collected 30 minutes after childbirth, placental morphological indicators were obtained by immediate measurement and formula calculation, and cytokine mRNA expression was detected by real-time quantitative polymerase chain reaction (RT-qPCR) afterward. Generalized linear models and linear mixed models were analyzed for the relationships of maternal TPOAb in the first, second and third trimesters with placental indicators.

Results

Totally 2274 maternal-fetal pairs were included in the analysis of maternal TPOAb levels and placental morphology, and 2122 pairs were included in that of maternal TPOAb levels and placental cytokines. Maternal TPOAb levels in early pregnancy were negatively associated with placental length, thickness, volume, weight and disc eccentricity, while positively correlated with placental IL-6, TNF-α, CRP, CD68, MCP-1, IL-10, HO-1, HIF-1α and GRP78. In mid-pregnancy, maternal TPOAb levels were negatively correlated with placental length, width and area. In late pregnancy, maternal TPOAb levels were negatively correlated with placental length, area, volume and weight. Repeated measures analysis showed that maternal TPOAb positivity tended to increase placental TNF-α, CD68 and MCP-1 while decreasing placental length, width and area than TPOAb negativity. Repeated measures analysis showed that maternal TPOAb levels were positively correlated with placental IL-6, TNF-α, CD68, MCP-1, IL-10, HO-1, HIF-1α and GRP78, while negatively correlated with placental length, area, volume, weight, and disc eccentricity.

Conclusion

There may be trimester-specific associations between maternal TPOAb levels and placental morphology and inflammatory and oxidative stress responses. The effect of maternal TPOAb levels on placental morphology is present throughout pregnancy. Early pregnancy may be the critical period for the association between maternal TPOAb levels and placental inflammatory and oxidative stress responses.

Anti-TPO-mediated specific features of the placenta immunohistochemical profile and possible mechanisms for fetal loss

Passive transfer of antithyroid antibodies in mice leads to reproductive disorders. The purpose was to assess the placental tissue of experimental animals under the influence of the circulating thyroperoxidase antibodies. We performed an immunohistochemical examination of murine placentae after a passive transfer of thyroperoxidase antibodies. Placentae of mice that passively transferred IgG from healthy donors were used as control samples. For histological examination, 30 placental samples were selected from mice from the anti-TPO group and 40 placental samples were taken from mice from the IgG group. Immunostaining for VEGFR1, THBS 1, Laminin, CD31, CD34, FGF-β, CD56, CD14, TNF-α, kisspeptin, MCL 1, and Annexin V was performed. There is a significant decrease in the relative area of the expression of VEGFR1 (23.42 ± 0.85 vs. 33.44 ± 0.35, P < 0.01), thrombospondin 1 (31.29 ± 0.83 vs. 34.51 ± 0.75, P < 0.01), CD14 (25.80 ± 0.57 vs. 32.07 ± 0.36, P < .01), CD56 (30.08 ± 0.90 vs. 34.92 ± 0.15, P < 0.01), kisspeptin (25.94 ± 0.47 vs. 31.27 ± 0.57, P < 0.01), MCL 1 (29.24 ± 1.06 vs. 38.57 ± 0.79, P < 0.01) in the labyrinth zone of the placentae of mice from the anti-TPO group compared with control group. A significant increase in the relative expression of laminin and FGF-β was noted in the group of mice to which antibodies to thyroperoxidase were transferred, compared with the control group (36.73 ± 1.38 vs. 29.83 ± 0.94, P < 0.01 and 23.26 ± 0.61 vs. 16.38 ± 1.01, P < 0.01respectively). Our study exposed an imbalance of pro- and anti-angiogenic factors, decreased representation of placental macrophages and NK cells, abnormal trophoblast invasion processes, and insufficient expression of antiapoptotic factors in the placentae of mice in which anti-TPO antibodies were passively transferred.

Pregnancy outcomes and neonatal thyroid function in women with thyroid cancer: a retrospective study

BACKGROUND

Evidence regarding adverse pregnancy outcomes in patients with thyroid cancer has been conflicting, and the effect of thyroid dysfunction caused by thyroid hormone suppression therapy in terms of neonatal thyroid stimulating hormone (TSH) is unclear. This study aimed to investigate whether thyroid cancer was associated with adverse pregnancy outcomes and had an adverse effect on neonatal thyroid function.

METHODS

This was a retrospective study of 212 singleton pregnancies with thyroid cancer and 35,641 controls without thyroid cancer. Data on maternal pregnancy outcomes and neonatal outcomes were analyzed.

RESULTS

The median TSH level in the thyroid cancer group was significantly lower than that in the control group (0.87 µIU/mL vs. 1.17 µIU/mL; P < 0.001), while the FT4 level was higher than that in the control group (17.16 pmol/L vs. 16.33 pmol/L; P < 0.001). The percentage of thyroid peroxidase antibodies (TPOAb) positive in the thyroid cancer group was significantly higher than that in the control group (25.0% vs. 11.8%; P < 0.001). Pregnancies with thyroid cancer had a higher risk of late miscarriage (OR 7.166, 95% CI: 1.521, 33.775, P = 0.013), after adjusting maternal TPOAb positive, there was no statistical significance (OR 3.480, 95% CI: 0.423, 28.614, P = 0.246). Pregnancies with thyroid cancer had higher gestational weight gain (GWG) (14.0 kg vs. 13.0 kg, P < 0.001). Although there was no significant difference in the prevalence of gestational diabetes mellitus (GDM) (20.8% vs. 17.4%, P = 0.194), the oral glucose tolerance test (OGTT) showed that fasting plasma glucose and 2-hour value in the thyroid cancer group were higher than those in the control group (P = 0.020 and 0.004, respectively). There was no statistically significant difference in TSH between the thyroid cancer group and the control group, regardless of full-term newborns or preterm newborns.

CONCLUSIONS

Thyroid cancer might not have substantial adverse effects on pregnancy outcomes except for excessive GWG. No adverse effect on neonatal TSH was found, but the effect on long-term thyroid function and neuropsychological function in offspring need further study.

TRIAL REGISTRATION

Beijing Birth Cohort Study (ChiCTR220058395).

Relationship between thyroid antibody levels and ovarian reserve function in infertile chinese women with normal thyroid-stimulating hormone

BACKGROUND

To analyze the relationship of thyroid peroxidase antibody and thyroid globulin antibody levels with ovarian reserve function in infertile women.

METHODS

The data of 721 infertile patients who visited the hospital from January 2019 to September 2022 and whose thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) levels were in the normal range, were retrospectively analyzed. These patients were divided into two sets of three groups-the negative group, the 2.6 IU/ml ~ 100 IU/ml group and the TPOAb > 100 IU/ml group according to the TPOAb (thyroid peroxidase antibody) level, or the TgAb (anti-thyroglobulin antibody) negative group, the 14.58 IU/ml ~ 100 IU/ml group and the TgAb > 100 IU/ml group according to the TgAb level. They were compared for differences in ovarian reserve function index and thyroid hormone levels and analyzed for the relationship among thyroid antibody levels, ovarian reserve function, and thyroid hormone levels.

RESULTS

When TSH > 2.5 mIU/L, the bFSH (basal follicle stimulating hormone) level in the TPOAb > 100 IU/ml group (9.10 ± 1.16 IU/L) was significantly higher than that in the TPOAb negative group (8.12 ± 1.97 IU/L) and the 2.6 IU/ml ~ 100 IU/ml group (7.90 ± 1.48 IU/L) (P < 0.05); when TSH ≤ 2.5 mIU/L, there were no statistically significant differences in the bFSH and AFC (antral follicle count) number at different TPOAb levels. Whether TSH ≤ 2.5 mIU/L or TSH > 2.5 mIU/L, there were no statistically significant differences in the bFSH and AFC number at different TgAb levels (P > 0.05). FT3/FT4 ratio in the TPOAb 2.6 IU/ml ~ 100 IU/ml group and the > 100 IU/ml group was significantly lower than in the negative group. FT3/FT4 ratio in the TgAb 14.58 ~ 100 IU/ml group and the > 100 IU/ml group was also significantly lower than in the TgAb negative group (P < 0.05). TSH level in the TPOAb > 100 IU/ml group was significantly higher than in the 2.6 ~ 100 IU/ml group and the TPOAb negative group, but there were no statistically significant differences among different TgAb groups.

CONCLUSIONS

When TPOAb > 100 IU/ml and TSH > 2.5 mIU/L, it may affect the ovarian reserve function in infertile patients, and the mechanism may be associated with increased TSH and the imbalance of FT3/FT4 ratio caused by the increase of TPOAb.

The association between hypothyroidism and perinatal outcomes in patients with polycystic ovary syndrome

PURPOSE

To compare pregnancy, delivery, and neonatal outcomes in patients with polycystic ovary syndrome (PCOS) with and without concomitant hypothyroidism.

METHODS

A retrospective population-based cohort study including all women with an ICD-9 diagnosis of PCOS in the US between 2004 and 2014, who delivered in the third trimester or had a maternal death. We compared women with a concomitant diagnosis of hypothyroidism to those without. Women with hyperthyroidism were excluded. Pregnancy, delivery, and neonatal outcomes were compared between the two groups.

RESULTS

Overall, 14,882 women met inclusion criteria. Among them, 1882 (12.65%) had a concomitant diagnosis of hypothyroidism, and 13,000 (87.35%) did not. Women with concomitant hypothyroidism, compared to those without, were characterized by increased maternal age (25.5% ≥ 35 years vs. 18%, p < 0.001, respectively), and had a higher rate of multiple gestations (7.1% vs. 5.7%, p = 0.023). Interestingly, pregnancy, delivery and neonatal outcomes were comparable between the groups, except for a higher rate of small-for-gestational-age (SGA) neonates in the group with hypothyroidism (4.1% vs. 3.2%, p = 0.033) (Tables 2 and 3). In a multivariate logistic regression adjusting for potential confounders, hypothyroidism was no longer found to be associated with SGA (adjusted odds ratio [aOR] 1.32, 95% confidence interval [CI] 0.99-1.75, p = 0.057), but was found to increase the odds for preeclampsia (aOR 1.30, 95% CI 1.06-1.59, p = 0.012).

CONCLUSIONS

In patients with PCOS, concomitant hypothyroidism significantly increases the risk for preeclampsia. Unexpectedly, other pregnancy complications commonly increased by hypothyroidism were not increased in women with PCOS, likely due to the inherent elevated baseline pregnancy risks of PCOS.

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 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.

Thyroid hormones: Metabolism and transportation in the fetoplacental unit

The thyroid hormones (THs), thyroxine (T4) and triiodothyronine (T3), are of vital importance for fetal development. The concentration of THs in fetal circulation varies throughout gestation and differs from the concentration in the maternal serum, indicating the presence of maternal-fetal thyroid homeostasis regulatory mechanisms in the placenta. The passage of THs from maternal circulation to fetal circulation is modulated by plasma membrane transporters, enzymes, and carrier proteins. Monocarboxylate transporter 8, iodothyronine deiodinases (DIO2 and DIO3), and transthyretin are especially involved in this maternal-fetal thyroid modulation, shown by a greater expression in the placenta. THs also play a role in placental development and as expected, abnormal variations in TH levels are associated with pregnancy complications and can result in damage to the fetus. Although new evidence regarding TH regulation during pregnancy and its effects in the mother, placenta, and fetus has been published, many aspects of these interactions are still poorly understood. The objective of this review is to provide an evidence-based update, drawn from current data, on the metabolism and transport of THs in the placenta and their vital role in the maternal-fetal relationship.

The findings about relationship between autoimmune thyroid disease and first-trimester aneuploidy results

Aim: The aim of this study was to investigate the relationship between thyroid autoantibody and first-trimester aneuploidy results. Thyroid autoimmunity (TAI) is the most common autoimmune disorder. Patients with TAI are usually euthyroid. Thyroid peroxidase (TPO-Ab) in patients with or without thyroid dysfunction is associated with infertility, recurrent embryo implantation failure, and early pregnancy loss. The impact of TPO-Ab on first-trimester aneuploidy test results needs to be studied. Material and Method: This retrospective case-control study was conducted between December 2019 and May 2022. Patients with thyroid autoantibody positivity (n=112) were included in the study as the case group. The control group was selected from age and body mass index (BMI)-matched patients (n=130). Nuchal translucency (NT), crown rump length (CRL), pregnancy-associated plasma protein A (PAPP-A) and free beta subunit of human chorionic gonadotropin (β-hCG)) values were compared between the two groups. Results: This study included two hundred forty two age-matched (29.86±4.51) and BMI-matched (23.96±2.34) women. There was no statistically significant difference between groups in terms of free thyroxine (FT4), PAPP-A and free β-hCG (p>0.05). NT as a marker for major chromosomal defects and CRL were comparable in case and control groups (p>0.05). Conclusion: There is no statistically significant relationship between thyroid autoimmune diseases and the first-trimester aneuploidy results.

TSH and FT4 Reference Intervals in Pregnancy: A Systematic Review and Individual Participant Data Meta-Analysis

CONTEXT

Interpretation of thyroid function tests during pregnancy is limited by the generalizability of reference intervals between cohorts due to inconsistent methodology.

OBJECTIVE

(1) To provide an overview of published reference intervals for thyrotropin (TSH) and free thyroxine (FT4) in pregnancy, (2) to assess the consequences of common methodological between-study differences by combining raw data from different cohorts.

METHODS

(1) Ovid MEDLINE, EMBASE, and Web of Science were searched until December 12, 2021. Studies were assessed in duplicate. (2) The individual participant data (IPD) meta-analysis was performed in participating cohorts in the Consortium on Thyroid and Pregnancy.

RESULTS

(1) Large between-study methodological differences were identified, 11 of 102 included studies were in accordance with current guidelines; (2) 22 cohorts involving 63 198 participants were included in the meta-analysis. Not excluding thyroid peroxidase antibody-positive participants led to a rise in the upper limits of TSH in all cohorts, especially in the first (mean +17.4%; range +1.6 to +30.3%) and second trimester (mean +9.8%; range +0.6 to +32.3%). The use of the 95th percentile led to considerable changes in upper limits, varying from -10.8% to -21.8% for TSH and -1.2% to -13.2% for FT4. All other additional exclusion criteria changed reference interval cut-offs by a maximum of 3.5%. Applying these findings to the 102 studies included in the systematic review, 48 studies could be used in a clinical setting.

CONCLUSION

We provide an overview of clinically relevant reference intervals for TSH and FT4 in pregnancy. The results of the meta-analysis indicate that future studies can adopt a simplified study setup without additional exclusion criteria.

Effects of Levothyroxine Therapy on Pregnancy and Neonatal Outcomes in Subclinical Hypothyroidism

Purpose

To assess the effects of levothyroxine (LT4) therapy on pregnancy and neonatal outcomes in pregnant women with subclinical hypothyroidism (SCH) who had different thyroid peroxidase antibody (TPOAb) status.

Methods

The data of pregnant women from the Chengdu Hospital of Integrated Traditional Chinese and Western Medicine between January 2017 and August 2019 were collected. SCH was defined as 11.88 < free thyroxine (FT4) < 20.06pmol/L in conjunction with thyroid-stimulating hormone (TSH) >4.00 mU/L. Some clinical characteristics have been collected, including body mass index (BMI) before pregnancy, number of pregnancies, number of miscarriages (spontaneous abortion), parity, family history of diabetes, history of smoking, history of drinking, TSH, FT4, and TPOAb levels. The prevalence of pregnancy and neonatal outcomes in the LT4 and non-LT4 groups, and in the LT4 and euthyroid control groups were compared, respectively. Univariate and multivariate logistic regression analyses were used to assess the effects of LT4 therapy on pregnancy and neonatal outcomes in SCH pregnant women with TPOAb.

Results

A total of 985 subjects were enrolled and divided into LT4 group with 478 patients, non-LT4 group with 156 patients and euthyroid control group with 351 patients. The prevalence of amniotic fluid abnormalities and premature delivery in the LT4 group was lower than that in the non-LT4 group in participants with TPOAb-positive (TPOAb⁺). After adjusting age, BMI prior to pregnancy, number of pregnancies, number of miscarriages, parity, TSH and FT4 level, the SCH pregnant women with TPOAb⁺ in the LT4 group had a lower risk of amniotic fluid abnormalities and premature delivery than that in the non-LT4 group.

Conclusion

LT4 therapy could reduce the risk of premature delivery and amniotic fluid abnormalities in the SCH pregnant women with TPOAb⁺. However, more randomized trials are required to confirm this association before the unequivocal advocacy of LT4 therapy in pregnant women with SCH.

Preconception Counseling and Care for Pregnant Women with Thyroid Disease

Thyroid disease is associated with adverse maternal and fetal outcomes. Appropriate reference ranges should be used for the interpretation of test results, although universal screening for thyroid dysfunction is not warranted. Overt thyroid dysfunction requires careful consideration of medication adjustments and close monitoring. Mild thyroid hypofunction has been linked to adverse pregnancy outcomes including preterm delivery, and poor neurocognition in the offspring. This review summarizes the most recent evidence on the counseling and management of women with thyroid disease before and during pregnancy and highlights the areas of controversy in need of further research.

Impact of Thyroid Function on Pregnancy and Neonatal Outcome in Women with and without PCOS

Background: Women with polycystic ovary syndrome (PCOS) are more prone to autoimmune thyroiditis, and both disorders lead to subfertility and pregnancy-related complications. The aim of this study was to investigate whether mothers with and without PCOS and their offspring have comparable thyroid parameters at term and how thyroid parameters are associated with perinatal outcome in this population. Methods: This cross-sectional observational study was performed in a single academic tertiary hospital in Austria. Seventy-nine pregnant women with PCOS and 354 pregnant women without PCOS were included. Blood samples were taken from the mother and cord blood at birth. Primary outcome parameters were maternal and neonatal thyroid parameters at delivery. Secondary outcome parameters were the composite complication rate per woman and per neonate. Results: Thyroid dysfunction was more prevalent among PCOS women (p < 0.001). At time of birth, free triiodothyronine (fT3) levels were significantly lower in PCOS than in non-PCOS women (p = 0.005). PCOS women and their neonates had significantly higher thyreoperoxidase antibody (TPO-AB) levels (p = 0.001). Women with elevated TPO-AB had a significantly higher prevalence of hypothyroidism (p < 0.001). There was a significant positive correlation between maternal and neonatal free thyroxine, fT3 and TPO-AB levels. There were no significant differences in thyroid parameters between women or neonates with or without complications. Conclusions: Our results demonstrate a higher prevalence of thyroid dysfunction and autoimmunity in PCOS women, supporting a common etiology of both disorders. We were not able to show an association between complication rate and thyroid parameters.

Assessing maternal thyroid function and its relationship to duration of the first stage of labor

INTRODUCTION

Maternal thyroid function plays a critical role in the normal labor process. Whether maternal thyroid function affects the duration of the first stage of labor is still unknown.

METHODS

Maternal serum levels of free thyroxine (FT4), thyroid-stimulating hormone (TSH) and thyroid peroxidase antibody (TPOAb) were detected in 31,382 pregnant women. A multiple linear regression model was applied to investigate the effect of maternal thyroid function on the duration of the first stage of labor.

RESULTS

FT4 level in the second trimester and in the third trimester was found to be negatively associated with duration of the first stage of labor (β = -1.30 h, 95% CI: -2.28, -0.32, P < 0.01; β = -0.35 h, 95% CI: -0.61, -0.10, P < 0.01). TSH level in the third trimester was found to be positively associated with the duration of the first stage of labor (β = 0.12 h, 95% CI: 0.06, 0.18, P < 0.001). Per unit increase in TPOAb (IU/mL) in the second trimester and in the third trimester was significantly associated with prolonged first stage of labor (β = 0.08 h, 95% CI: 0.01, 0.14, P = 0.02; β = 0.09 h, 95% CI: 0.02, 0.15, P = 0.01). For pregnant women suffering from subclinical hypothyroidism combined without TPOAb, TSH level in the third trimester exhibited a significant positive association with the length of the first stage of labor (β = 2.44 h, 95% CI: 0.03, 4.84, P = 0.04).

CONCLUSIONS

These findings suggest that maternal FT4, TSH and TPOAb might be important predictors of the first stage of labor.

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.

Association of thyroid peroxidase antibodies with the rate of first-trimester miscarriage in euthyroid women with unexplained recurrent spontaneous abortion

BACKGROUND

Unexplained recurrent spontaneous abortion is a serious reproductive problem of unknown etiology. Thyroid peroxidase antibodies (TPO-Ab) may be associated with pregnancy outcomes in unexplained recurrent spontaneous abortion with normal thyroid function.

OBJECTIVE

This study aimed to investigate the relationship between TPO-Ab and the first trimester miscarriage rate/live birth rate in women of unexplained recurrent spontaneous abortion with normal thyroid function.

METHODS

We retrospectively analyzed the clinical data of 297 women who met our strict inclusion criteria, comparing the first trimester miscarriage rate/live birth rate between the TPO-Ab positive and TPO-Ab negative groups. For the same purpose, we also performed subgroup analysis.

RESULTS

Of the included women, 76 (25.6%) were TPO-Ab positive, and 221 (74.4%) were negative. First trimester miscarriage rate differed between the two groups (36.8% vs 24.0%, RR = 1.54, 95% CI: 1.05-2.24, P = 0.030). In the younger subgroup (<35 years) and the primary RSA subgroup, First trimester miscarriage rate was also higher in the TPO-Ab positive group (33.3% vs 19.0%, RR = 1.75, 95% CI: 1.07-2.87, P = 0.030; 36.5% vs 21.7%, RR = 1.69, 95% CI: 1.10-2.58, P = 0.020). While the live birth rate was lower in women with TPO-Ab positive, the difference did not reach statistical significance, even in the subgroup analysis.

CONCLUSION

Our results suggest that TPO-Ab is associated with first trimester miscarriage rate in euthyroid women with unexplained recurrent spontaneous abortion.

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.

Placental pathologic features in thyroid autoimmunity

INTRODUCTION

Data on placental pathologic features associated with thyreoperoxidase antibodies (TPO Ab) and/or hypothyroidism are limited. The objective of the study was to analyze placental pathologic features of women with TPO Ab positivity.

METHODS

Prospective case-control observational study of pregnancy outcome among women screened for TPO Ab positivity and/or isolated hypothyroidism (TSH>4mU/L) during the first trimester of pregnancy. Placenta pathologic findings were recorded according to standard classification.

RESULTS

The overall rates of TPO Ab positivity and isolated hypothyroidism with negative TPO Ab were 9.6% (86/899) and 2.7% (24/899), respectively. Among TPO Ab positive cases, 77.9% (67/86) and 22.1% (19/86) had TSH ≥2.5mU/L or <2.5mU/L, respectively. Compared to controls, mean first and second trimester uterine artery Doppler pulsatility indices (PI) were higher, placental volume and area were lower among cases with TSH≥2.5mU/L. The rates of fetal growth restriction (FGR)/small for gestational age (SGA) (20/67 versus 8/110, Adjusted Odds Ratio (AdjOR) = 10.8,95%CI = 2.7-44), placental pathological features suggesting decidual vasculopathy (37/67 versus 27/110, AdjOR = 2.7,95%CI = 1.1-6.8) or severe maternal vascular malperfusion (MVM) (22/67 versus 9/110, AdjOR = 5.8,95%CI = 1.6-20.1) were higher among cases with TSH ≥2.5mU/L than in controls. Similar results were obtained comparing overall TPO Ab positive subjects to controls. The increased risk of defective placentation and FGR associated with TPO Ab was independent of simultaneous presence of antinuclear antibodies (ANA) and TSH concentration.

DISCUSSION

First trimester TPO Ab positivity was associated with increased rates of abnormal uterine artery Doppler PI and placental features of MVM. This association was independent of TSH concentration and presence of ANA.

Associations of Hypothyroxinemia With Risk of Preeclampsia-Eclampsia and Gestational Hypertension

OBJECTIVE

To investigate the association between hypothyroxinemia and the risk of preeclampsia-eclampsia and gestational hypertension.

DESIGN

Historical cohort study.

METHODS

The study included pregnant individuals who delivered live-born singletons and had at least one thyroid function assessment during pregnancy at a tertiary hospital. Hypothyroxinemia was defined as thyroid-stimulating hormone (TSH) levels within the normal reference range and free thyroxine (FT4) levels lower than the tenth percentile. Risk ratios (RRs) with 95% confidence intervals (95% CIs) for preeclampsia-eclampsia and gestational hypertension between women with and without a diagnosis of hypothyroxinemia during pregnancy were estimated using a generalized estimating equation model.

RESULTS

A total of 59,463 women with live-born singletons were included in the analysis. Logistic regression models with restricted cubic spline suggested that there was a U-shaped association between FT4 levels and preeclampsia-eclampsia risk. Compared with euthyroid women, those with hypothyroxinemia had an increased risk of preeclampsia-eclampsia (RR = 1.16, 95% CI: 1.02-1.31), and the risk increased with the increasing severity of hypothyroxinemia (p for trend < 0.001). Moreover, persistent hypothyroxinemia from the first to second trimesters was associated with an increased risk of preeclampsia-eclampsia (RR = 1.37, 95% CI: 1.03-1.83), especially for women with severe hypothyroxinemia (RR = 1.70, 95% CI: 1.12-2.58). In contrast, there was no association between hypothyroxinemia and gestational hypertension.

CONCLUSION

Our study suggested that hypothyroxinemia was only associated with an increased risk of preeclampsia-eclampsia, especially in women with persistent hypothyroxinemia in the first half of pregnancy. Analyses of the associated risk of gestational hypertension with hypothyroxinemia were not significant.