Management of thyrotoxicosis during pregnancy

Global research landscape and emerging trends in Graves' disease: A bibliometric analysis

BACKGROUND

Graves' disease is a prevalent thyroid disorder and is the primary cause of hyperthyroidism. Significant progress has been made in understanding the epidemiology, pathogenesis, diagnosis, treatment, and prognosis of this disease. However, bibliometric analyses on Graves' disease are lacking. We aimed to comprehensively summarize the research, progression, and focal points of Graves' disease through data mining and integrated analysis of the existing literature.

METHODS

We retrieved relevant literature on Graves' disease from 2003 to 2023 from the Web of Science database. We performed bibliometric analysis using CiteSpace and the R package Bibliometrix.

RESULTS

We identified 10,901 publications from 132 countries, with a steady rise in the number of publications over the past 5 years. The US leads in publication volume, with the University of California System being the primary contributing institution. The journal Thyroid had the highest publication output, while the Journal of Clinical Endocrinology and Metabolism was the most frequently cited. These publications involved 2305 authors, with Antonelli Alessandro and Smith Terry being the most prolific. The most frequently cited articles were the "2016 American Thyroid Association guidelines for diagnosis and management of hyperthyroidism and other causes of thyrotoxicosis" and the "Thyroid Association/European Group on Graves' orbitopathy guidelines for the management of Graves' orbitopathy." Analysis of the bursts of cited references, keywords, and their clustering revealed that research on Graves' disease predominantly centers on clinical management, thyroid-stimulating hormone receptors, thyroid hormones, autoimmunity and inflammation, Graves' ophthalmopathy, thyroid nodules, and thyroid cancer.

CONCLUSION

This is the first comprehensive bibliometric study to summarize progress and trends in Graves' disease research. These results highlight recent research hotspots and promising directions, thereby providing a valuable reference for other scholars.

Preconceptional Counseling in Women with Hyperthyroidism

Preconception evaluation of couples wishing to conceive is an important step toward a healthy pregnancy and it is especially important in people with a chronic condition or at genetic risk. The most common endocrine disorders in women at reproductive age are those involving the thyroid gland and it is well recognized that hyperthyroidism (HT), over-function of the thyroid gland, is associated with risks of maternal, fetal, and neonatal complications. The aim of this paper is to review the latest evidence regarding the components of preconception counseling in women with HT that contemplate a pregnancy. We also want to raise awareness among healthcare professionals about the importance of periconceptional counseling in improving pregnancy outcomes and avoid maternal and fetal complications related to thyroid dysfunction. In women with Graves' disease seeking pregnancy, it is essential to discuss all the treatment options along with the associated risks and benefits. Extensive prospective studies are still needed to understand the implications of current recommended strategies for the management of HT in preconception and during pregnancy.

Fetal Hyperthyroidism with Maternal Hypothyroidism: Two Cases of Intrauterine Therapy

Fetal hyperthyroidism can occur secondary to maternal autoimmune hyperthyroidism. The thyroid-stimulating hormone receptor antibody (TRAb) transferred from the mother to the fetus stimulates the fetal thyroid and causes fetal thyrotoxicosis. Fetuses with this condition are difficult to detect, especially after maternal Graves disease therapy. Here, we present two cases of fetal hyperthyroidism with maternal hypothyroidism and review the assessment and intrauterine therapy for fetal hyperthyroidism. Both women were referred at 22+ and 23+ weeks of gestation with abnormal ultrasound findings, including fetal heart enlargement, pericardial effusion, and fetal tachycardia. Both women had a history of Graves disease while in a state of hypothyroidism with a high titer of TRAb. A sonographic examination showed a diffusely enlarged fetal thyroid with abundant blood flow. Invasive prenatal testing revealed no significant chromosomal aberration. Low fetal serum TSH and high TRAb levels were detected in the cord blood. Fetal hyperthyroidism was considered, and maternal oral methimazole (MMI) was administered as intrauterine therapy, with the slowing of fetal tachycardia, a reduction in fetal heart enlargement, and thyroid hyperemia. During therapy, maternal thyroid function was monitored, and the dosage of maternal levothyroxine was adjusted accordingly. Both women delivered spontaneously at 36+ weeks of gestation, and neonatal hyperthyroidism was confirmed in both newborns. After methimazole and propranolol drug treatment with levothyroxine for 8 and 12 months, both babies became euthyroid with normal growth and development.

Hyperthyroidism in Danish Pregnant Women During a 20-Year Period

CONTEXT

Hyperthyroidism in pregnancy is a clinical concern, and surveillance of any change in the occurrence of hyperthyroidism in pregnancy is important, especially when a mandatory iodine fortification (IF) program is implemented such as in Denmark in the year 2000.

OBJECTIVE

To investigate any change in the occurrence of hyperthyroidism and the use of antithyroid drugs (ATDs) in Danish pregnant women during a 20-year period before and after the implementation of IF.

METHODS

A nationwide register-based cohort (1997-2016) and 2 birth cohorts with biochemical data (the Danish National Birth Cohort, 1997-2003, and the North Denmark Region Pregnancy Cohort, 2011-2015) were used to study maternal use of ATDs in pregnancy and frequency of early pregnancy biochemical hyperthyroidism during a 20-year period prior to and after the implementation of mandatory IF.

RESULTS

In the nationwide cohort, the adjusted odds ratio (aOR) for treatment with ATDs was 1.51 (95% CI, 1.30-1.74) after mandatory IF (2001-2004) compared with baseline (1997-1999). The increase was more pronounced in the previously moderately iodine-deficient West Denmark (aOR 1.67; 95% CI, 1.36-2.04) than the mildly deficient East Denmark (aOR 1.30; 95% CI, 1.06-1.60) and returned to baseline levels at the end of follow-up in both regions. No time-related difference in early pregnancy biochemical hyperthyroidism was observed.

CONCLUSION

The use of ATDs in Danish pregnant women increased following the implementation of IF and then leveled out. Results comply with observations in the general Danish population and suggest that IF influences the occurrence of autoimmune hyperthyroidism in younger individuals.

Effectiveness and potential mechanism of Jiawei-Xiaoyao-San for hyperthyroidism: a systematic review

Objectives

To evaluate the effectiveness and potential mechanism of traditional Chinese medicine Jiawei-Xiaoyao-San (JWXYS) as an adjunct or mono- therapy for antithyroid drugs (ATDs) in the treatment of hyperthyroidism.

Methods

Eight databases and three trial registries were searched from inception until May 2023. Randomized controlled trials (RCTs) were included and meta-analysis was conducted using RevMan 5.4 and Stata 14.0. The Cochrane risk of bias (ROB) tool 1.0 and GRADE tool was used for quality appraisal. The findings from case reports using mono-JWXYS and pharmacological studies were summarized in tables.

Results

Thirteen RCTs with 979 participants were included. The majority of the included studies were assessed as high risk of bias in one ROB domain. Compared with ATDs, JWXYS plus ATDs resulted in lower free triiodothyronine (FT3) (MD = -1.31 pmol/L, 95% CI [-1.85, -0.76]; low-certainty), lower free thyroxine (MD = -3.24 pmol/L, 95% CI [-5.06, -1.42]; low-certainty), higher thyroid stimulating hormone (MD = 0.42 mIU/L, 95% CI [0.26, 0.59]; low-certainty), higher effectiveness rate of traditional Chinese medicine syndrome (RR = 1.28, 95% CI [1.08, 1.52]; low-certainty), lower goiter score (MD = -0.66, 95% CI [-1.04, -0.29]; very low-certainty), lower thyrotrophin receptor antibody (SMD = -0.44, 95% CI [-0.73, -0.16]; low-certainty) and fewer adverse events (AEs) (RR = 0.34, 95% CI [0.18, 0.67]; moderate-certainty). Compared with regular dosage of ATDs, JWXYS plus half-dose ATDs resulted in fewer AEs (RR = 0.24, 95% CI [0.10, 0.59]; low-certainty). Compared with ATDs in 1 trial, JWXYS resulted in higher FT3, lower goiter score and fewer AEs. Three case reports showed that the reasons patients sought TCM-only treatment include severe AEs and multiple relapses. Three pharmacological studies demonstrated that JWXYS restored Th17/Treg balance, lowered deiodinases activity, regulated thyroid cell proliferation and apoptosis, and alleviated liver oxidative stress in mouse or rat models.

Conclusion

JWXYS may enhance the effectiveness of ATDs for hyperthyroidism, particularly in relieving symptoms and reducing AEs. Mono-JWXYS is not recommended except in patients intolerant to ATDs. The findings should be interpreted with caution due to overall high risk of bias. Further pharmacological studies with more reliable models are needed.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42023394923.

Management of foetal hyperthyroidism in a mother with autoimmune hypothyroidism: A case report

Foetal hyperthyroidism is mediated by transplacental passage of thyroid stimulating antibodies (TSAbs) and affects mothers with autoimmune (AI) thyroid disease. We report a case of a 33-year-old woman with a history of AI hypothyroidism and raised TSI after 2 stillbirths with suspect foetal hyperthyroidism. At 20.5 gestational weeks (GW) of her third pregnancy, foetal tachycardia and goitre were detected. TSI levels were 30.9mUI/mL. Methimazole (MMI) was started and adjusted based on ultrasound signs (foetal heart rate and thyroid gland vascularisation). The neonate was born at 35GW and cord blood revealed decreased TSH and normal free T4. MMI was started in the neonate at 2 days of life due to the appearance of asymptomatic hyperthyroidism. This case illustrates a rare recurrence of foetal hyperthyroidism in a mother with AI hypothyroidism. Pregestational thyroidectomy, TSAbs determination, early ultrasound diagnosis and foetal therapy helped us to improve obstetric outcomes.

Advances in the differential diagnosis of transient hyperthyroidism in pregnancy and Graves' disease

BACKGROUND

The occurrence of thyrotoxicosis during pregnancy is mainly attributed to gestational transient thyrotoxicosis (GTT) and Graves' disease (GD). It is important to distinguish between GTT and Graves' disease because the two diseases are treated very differently. However, a gold standard for the differential diagnosis of the two diseases is currently lacking, and the most common method of differentiation is based on past medical history and clinical presentation combined with thyroid-related antibodies.

METHODS

A literature search of the electronic databases PubMed, Embase, Medline, Google Scholar, Cochrane Library, China Knowledge Infrastructure, Wanfang Database, Chinese Scientific Journals Full Text Database and China Biomedical CD-ROM was performed. The search period ranged from journal inception until 2022. We used the following search terms in "All fields": {["thyroid" (common field) OR "thyroid" (subject line)] OR "hyperthyroidism" (common field)} AND {["pregnancy" (title) OR "pregnancy" (title)] AND "one over" (common field)} OR {["pregnancy" (common field) OR "pregnancy" (common field) OR "pregnancy" (subject line)] AND "Graves'" (common field)}.

RESULTS

In recent years, some clinical studies at home and abroad have proposed other meaningful differential indicators, such as thyroid stimulating hormone, chorionic gonadotropin, thyroid hormone levels and thyroid ultrasound.

CONCLUSION

The differential diagnostic significance of each of these indicators is summarised here with the goal of providing a better reference for the differential diagnosis of hyperthyroidism during pregnancy in clinical practice.

Hyperthyroidism in pregnancy: design and methodology of a Danish multicenter study

BACKGROUND

Graves' disease (GD) is the main cause of hyperthyroidism in women of the fertile age. In pregnant women, the disease should be carefully managed and controlled to prevent maternal and fetal complications. Observational studies provide evidence of the adverse effects of untreated hyperthyroidism in pregnancy and have in more recent years substantiated a risk of teratogenic side effects with the use of antithyroid drugs (ATDs). These findings have challenged the clinical recommendations regarding the choice of treatment when patients become pregnant. To extend observational findings and support future clinical practice, a systematic collection of detailed clinical data in and around pregnancy is needed.

METHODS

With the aim of collecting clinical and biochemical data, a Danish multicenter study entitled 'Pregnancy Investigations on Thyroid Disease' (PRETHYR) was initiated in 2021. We here describe the design and methodology of the first study part of PRETHYR. This part focuses on maternal hyperthyroidism and recruits female patients in Denmark with a past or present diagnosis of GD, who become pregnant, as well as women who are treated with ATDs in the pregnancy, irrespective of the underlying etiology. The women are included during clinical management from endocrine hospital departments in Denmark, and study participation includes patient questionnaires in pregnancy and postpartum as well as review of medical records from the mother and the child.

RESULTS

Data collection was initiated on November 1, 2021 and covered all five Danish Regions from March 1, 2022. Consecutive study inclusion will continue, and we here report the first status of inclusion. As of November 1, 2022, a total of 62 women have been included in median pregnancy week 19 (interquartile range (IQR): 10-27) with a median maternal age of 31.4 years (IQR: 28.5-35.1). At inclusion, 26 women (41.9%) reported current use of thyroid medication; ATDs (n = 14), Levothyroxine (n = 12).

CONCLUSION

This report describes a newly established systematic and nationwide collection of detailed clinical data on pregnant women with hyperthyroidism and their offspring. Considering the course and relatively low prevalence of GD in pregnant women, such nationwide design is essential to establish a sufficiently large cohort.

Gestational Transient Thyrotoxicosis Complicated by Thyroid Storm in a Patient With Hyperemesis Gravidarum

We describe a patient with gestational transient thyrotoxicosis (GTT) associated with hyperemesis gravidarum (HG) in a twin gestation complicated by thyroid storm resulting in intrauterine fetal demise. GTT is a well-documented complication of the first trimester of pregnancy that may affect up to 60% of pregnancies with HG. Typically, GTT is not associated with unfavorable maternal or fetal outcomes and has a spontaneous resolution. Aside from supportive care, the use of antithyroid drugs (ATD) in GTT is not regularly recommended. Although to our knowledge one similar case has been reported in the literature, the incidence of thyroid storm in GTT has not yet been established. Our case highlights that, although rare, GTT may be complicated by thyroid storm resulting in adverse maternal and fetal outcomes. Our case further suggests that consideration of ATD use in GTT should be given in pregnancies with higher serum human chorionic gonadotropin (hCG) concentration as occurs in HG and multiple pregnancies.

Autoimmune disease and risk of postpartum venous thromboembolism

Background

The risk of pregnancy-related mortality in the United States has nearly doubled since 1990, with venous thromboembolism (VTE) accounting for approximately 10% of these deaths.

Objectives

The objective of this study was to assess whether preexisting autoimmune disease is a risk factor for postpartum VTE.

Methods

Using the MarketScan Commercial and Medicare Supplemental administrative databases, a retrospective cohort study analyzed whether postpartum persons with autoimmune disease had a higher risk of postpartum VTE incidence than postpartum persons without autoimmune disease. Using International Classification of Diseases codes, we identified 757,303 individuals of childbearing age who had a valid delivery date with at least 12 weeks of follow-up.

Results

Individuals were, on average, 30.7 years old (SD, 5.4), and 3.7% (N = 27,997 of 757,303) of them had evidence of preexisting autoimmune disease. In covariate-adjusted models, postpartum persons with preexisting autoimmune disease had higher rates of postpartum VTE than postpartum persons without autoimmune disease (hazard ratio [HR], 1.33; 95% CI, 1.07-1.64). When analyzed by individual autoimmune disease, those with systemic lupus erythematosus (HR, 2.49; 95% CI, 1.47-4.21) and Crohn's disease (HR, 2.49; 95% CI, 1.34-4.64) were at an elevated risk of postpartum VTE compared with those without autoimmune disease.

Conclusion

Autoimmune disease was associated with a higher rate of postpartum VTE, with evidence that the association was most pronounced among individuals with systemic lupus erythematosus and Crohn's disease. These findings suggest that postpartum persons of childbearing age with autoimmune disease may require more monitoring and prophylactic care after delivery to prevent potentially fatal VTE events.

[Thyroid disease during pregnancy]

Thyroid disease is the second most endocrinopathy during pregnancy 1. Thyroid dysfunction affects 2-3 % of pregnant women 2. Early diagnosis and initiation of therapy are important due to the potential complications in both mother and fetus. This article provides an overview of current recommendations regarding thyroid diagnostics and constellations during pregnancy that require therapy.

A practical approach to the management of thyroid dysfunction during pregnancy

Pregnancy has an important impact on the thyroid gland and its function. Thyroid activity changes as a consequence of the novel physiological state of pregnancy and requires a complex hormonal and metabolic adaptation, which is possible only in the presence of a perfectly functioning thyroid gland. In fact, thyroid function is crucial for the success of the implantation and the progression of pregnancy. Abnormal thyroid function is very common among childbearing age women, explaining the high incidence of thyroid diseases that occur during pregnancy. Aim of this work is to analyze the adaptive events that characterize the thyroid function during pregnancy, exploring their hormonal, metabolic and molecular mechanisms. Moreover, the interpretation of the laboratory data necessary to monitor the thyroid functioning during normal pregnancy or in the presence of thyroid abnormalities will be discussed.

Further understanding of thyroid function in pregnant women

INTRODUCTION

Normal thyroid status throughout pregnancy is important for both maternal and fetal health. Despite the bulk of contemporary research honing on thyroid function in gestation and the relevant disorders, there are still gaps in our current knowledge about the etiology and treatment of thyroid diseases in pregnant women.

AREAS COVERED

This article analyzes the adaptation of the thyroid gland to gestational physiological changes and attempts to explain the effect of several factors on thyroid function in pregnancy. It also stresses proper utilization and interpretation of thyroid tests during pregnancy and underlines the significance of proper screening and treatment of pregnant women aiming at favorable health outcomes.

EXPERT OPINION

Appropriate strategies for diagnosing and treating thyroid disease in pregnancy are important. Laboratory thyroid testing plays a leading role, but test results should be interpreted with caution. Given the possible serious maternal and fetal/neonatal complications of thyroid disease in pregnancy, we recommend universal screening with TSH measurements of all pregnant women. Additional assessment with determination of the levels of free thyroid hormones and thyroid antibodies may be necessary under certain conditions. The economic burden of such interventions should be considered.

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.

Hyperthyroidism in Pregnancy: The Delicate Balance between Too Much or Too Little Antithyroid Drug

Overt hyperthyroidism (HT) during pregnancy is associated with a risk of maternal–fetal complications. Antithyroid drugs (ATD) have a potential risk for teratogenic effects and fetal–neonatal hypothyroidism. This study evaluated ATD treatment and thyroid function control during pregnancy, and pregnancy outcome in women with HT. Patients and methods: A retrospective analysis of 36 single fetus pregnancies in 29 consecutive women (median age 30.3 ± 4.7 years) with HT diagnosed before or during pregnancy; a control group of 39 healthy euthyroid pregnant women was used. Results: Twenty-six women had Graves’ disease (GD, 33 pregnancies), 1 had a hyperfunctioning autonomous nodule, and 2 had gestational transient thyrotoxicosis (GTT). Methimazole (MMI) was administered in 22 pregnancies (78.5%), Propylthiouracil (PTU) in 2 (7.1%), switch from MMI to PTU in 4 (14.2%), no treatment in 8 pregnancies (3 with subclinical HT, 5 euthyroid with previous GD remission before conception). In the 8 pregnancies of GD patients diagnosed during gestation or shortly before (<6 weeks), i.e., with fetal exposure to uncontrolled HT, there was 1 spontaneous abortion at 5 weeks (3.4% of all ATD-treated pregnancies), and 1 premature delivery at 32 weeks with neonatal death in 24 h (3.4%); 1 child had neonatal hyperthyroidism (3.3% of live children in GD women) and a small atrial sept defect (4% of live children in ATD treated women). In women treated more than 6 months until conception (20 pregnancies): (a) median ATD doses were lower than those in women diagnosed shortly before or during pregnancy; (b) ATD was withdrawn in 40% of pregnancies in trimester (T)1, all on MMI < 10 mg/day (relapse in 14.2%), and in up to 55% in T3; (c) TSH level was below normal in 37%, 35% and 22% of pregnancies in T1, T2 and T3 respectively; FT4 was increased in 5.8% (T1) and subnormal in 11.75% in T2 and T3; (d) no fetal birth defects were recorded; one fetal death due to a true umbilical cord knot was registered. Mean birth weight was similar in both ATD-treated and control groups. Hyperthyroidism relapsed postpartum in 83% of GD patients (at median 3 ± 2.6 months). Conclusion: In hyperthyroid women with long-term ATD treatment before conception, drugs could be withdrawn in T1 in 40% of them, the thyroid function control was better, and pregnancy and fetal complications were rarer, compared to women diagnosed during pregnancy. Frequent serum TSH and FT4 monitoring is needed to maintain optimal thyroid function during pregnancy.

Hyperthyroidism management during pregnancy and lactation (Review)

Thyroid dysfunction is a significant public health issue, affecting 5-10 more women compared to men. The estimated incidence is up to 12% and only for women the treatment rises up to 4.3 billion dollars annually. Thyroid pathology can have a major impact on female fertility and it can only be detected when preconception tests are performed. Untreated or poorly treated hyperthyroidism in a mother can affect the fetal development and pregnancy outcome. Between 0.1 and 0.4% of the pregnancies are affected by clinical hyperthyroidism. Thyroid dysfunction is associated with higher rates of pregnancy loss. Hyperthyroidism can complicate fetal health problems intrauterinely and in the neonatal period. The TSH receptor is stimulated by TSH and HCG which has a similar structure. This can lead to gestational thyrotoxicosis. Hyperthyroidism can be treated with propylthiouracil or methimazole and in selected cases, surgical treatment or radioactive iodine can be chosen. In pregnancy, the most used treatment is represented by propylthiouracil which can be used from the first trimester. The aim of this review is to assess the current data regarding the impact of thyroid dysfunction on pregnancy and to synthesize the treatment options during pregnancy and lactation.