Pregnancy complicated by thyroid disease

Thyroid disorders during pregnancy can have potential adverse effects on the fetus, making recognition and treatment of paramount importance. Signs and symptoms of thyroid disease can be masked by pregnancy. Familiarity with thyroid function test values and their interpretation during normal pregnancy is necessary to discriminate between expected changes and pathological changes. Ongoing management of a pregnant woman with thyroid disease involves sign and symptom monitoring, thyroid function testing to adjust medication dosage, and patient education/counseling regarding the disease and its relationship to her pregnancy.     

Systematik der Diagnostik und Therapie von Schilddrüsenerkrankungen

Diseases of the thyroid are very common and in Germany one out of three adults has a goiter or thyroid nodules. Thyroid dysfunction, including its subclinical forms is found in up to 6% (hyperthyroidism) and up to 10% (hypothyroidism) of the population, respectively. The aim of a structured approach to patients is to obtain a diagnosis by evaluating morphological findings, thyroid dysfunction, signs suggestive of autoimmune disease or inflammation and accompanying disorders (notably, thyroid-associated orbitopathy). Euthyroid goiter and benign thyroid nodules may benefit from supplementation with iodine and thyroxine. Differentiated thyroid carcinoma is treated by thyroidectomy and subsequent radioiodine ablation. Antithyroid drugs are the primary treatment for Graves’ disease. Many cases of autoimmune thyroid diseases require thyroxine treatment.     

Autoimmunthyreoiditis und assistierte Reproduktion

Autoimmune thyroid diseases have an impact on fertility in both genders at different reproductive levels. This may affect menstrual disorders, miscarriage rates and sperm quality. The basic endocrine testing should therefore include a thyroid stimulating hormone (TSH) determination. Drug therapy of autoimmune thyroid disease improves the prospects of a reproductive medical treatment and helps to reduce the risk of miscarriage. Evidence of loss of libido and impotence in men should also be tested by a thyroid gland investigation.     

多囊卵巢综合征与甲状腺功能减退关系的研究进展

多囊卵巢综合征(PCOS)是一种发病多因性、病理生理和临床表现多样的内分泌综合征。研究显示,PCOS患者的甲状腺疾病发病率增高。早期的学者主要是对神经内分泌和免疫方面进行研究,认为PCOS可影响垂体-甲状腺功能轴,并使患者免疫系统受到过度刺激。近期新的研究在分子生物学水平上取得突破,认为PCOS患者的促性腺激素释放激素受体基因变异与甲状腺功能有关。同时,甲状腺功能的改变也可能影响PCOS患者排卵功能及胰岛素敏感性等。     

Treatment of maternal hyperthyroidism and fetal goiter

A fetal goitre is a potentially dangerous phenomenon because of mechanical obstruction and possible fetal thyroid function disorders. During pregnancy women with a history of Graves' disease under treatment with propylthiouracil (PTU) have an increased risk for fetal goitre. In this report a patient with Graves' disease diagnosed in early pregnancy and treated with PTU which resulted in a fetal goitre is described. The fetal thyroid status, investigated by percutaneous fetal umbilical cord blood sampling, was normal and the reduction of PTU dosage was sufficient to decrease goitre volume.     

Hipertiroidismo transitorio secundario a hiperemesis gravídica

Thyroid disorders during pregnancy are frequent due to significant changes in normal thyroid activity. One of these disorders is transient hyperthyroidism of hyperemesis gravidarum in the first few weeks of pregnancy, which is usually self-limiting.We present a case of longstanding and refractory hyperemesis gravidarum with manifestations of hyperthyroidism, posing a difficult differential diagnosis with Graves’ disease.     

What the obstetrician/gynecologist should know about thyroid disorders

Thyroid disease is a common disorder faced by women of all ages. Because of its high incidence in women, recognizing and treating thyroid dysfunction often becomes the responsibility of the obstetrician/gynecologist. It is important that women's healthcare providers understand how the thyroid's function changes as a woman enters her reproductive years, as well as during pregnancy and menopause. Current guidelines for diagnosing and managing thyroid dysfunction and recommended treatment strategies are discussed in this review. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians. LEARNING OBJECTIVES: After completion of this educational activity, the obstetrician/gynecologist should be better able to evaluate normal thyroid physiology and pathophysiology of thyroid dysfunction; assess appropriate screening options for their patients; and diagnose and manage thyroid disorders common among reproductive-aged women.     

Obstetric management of thyroid disease

Timely treatment of thyroid disease during pregnancy is important in preventing adverse maternal and fetal outcome. At present, thyroid testing is performed on symptomatic pregnant women or those with a history of the disease. Hypothyroidism is very often subclinical in nature and not easily recognized without specific screening programs. Even mild maternal thyroid hormone deficiency may lead to neurodevelopment complications in the fetus. Early maternal thyroxine therapy might be beneficial in these women. The main diagnostic indicator of thyroid disease is the measurement of serum thyroid stimulating hormone and free thyroxine. Availability of gestation-age-specific thyroid stimulating hormone (TSH) thresholds is an important aid in the accurate diagnosis and treatment of thyroid dysfunction. Pregnancy-specific free thyroxine thresholds not presently available are also required. Gestational iodine deficiency is still prevalent in some areas of the United Kingdom. Thyroid peroxidase antibody (TPO Ab) in combination with thyroglobulin autoantibody (TgAb) is an accurate predictor of postpartum thyroiditis (PPT). Early screening and treatment of PPT may be justified on the grounds that it is relatively common and causes considerable postpartum morbidity. Large-scale intervention trials are urgently needed to assess the efficacy of preconception or early pregnancy screening for thyroid disorders. Target Audience: Obstetricians & Gynecologists, Family Physicians Learning Objectives: After completion of this article, the reader should be able to state that thyroid gland physiology changes with pregnancy, recall that levels of thyroid hormones are gestational-age related, and explain that accurate interpretation of both antepartum and postpartum levels of thyroid hormones are important in preventing pregnancy-related complication secondary to thyroid dysfunction and in the diagnosis and management of postpartum thyroiditis.     

Thyrotoxicosis in Pregnancy Presenting as Pancytopenia

EDITORIAL COMMENT: In spite of its rarity we accepted this case report for presentation to remind readers of the dire complications that can occur in a woman with thyrotoxicosis that has escaped recognition. It is a reminder that thyroid function should be tested in patients who present with severe medical emergencies of uncertain aetiology.
Summary: Delay in diagnosis of thyroid disease can result in morbidity and mortality. Thyroid disorders are not uncommon in the reproductive age group and therefore in pregnancy; recognition of both the common and the more unusual manifestations will optimize outcome.     

Endocrine disorders in pregnancy.

Disorders of the pituitary gland such as diabetes insipidus, pituitary adenomas, and hyperprolactinemia, disorders of the thyroid gland such as Graves' disease and hypothyroidism, and diseases of the adrenal gland such as adrenocortical insufficiency and Cushing's syndrome can complicate pregnancy. The goals of this article were to provide a basic scientific understanding of the normal function of these endocrine glands, their pregnancy-related changes, and suggestions for diagnosis and treatment of maternal and fetal endocrine disorders during pregnancy. Antenatal recognition and appropriate management of the disorders that especially affect the fetus (i.e., maternal Graves' disease, fetal hypothyroidism, and congenital adrenal hyperplasia) is essential in order to prevent fetal and neonatal morbidity and mortality.     

Thyroid disorders in pregnancy

PURPOSE OF REVIEW: There is now increasing understanding of the association between not only overt, but also subclinical, thyroid disorders and dysfunction with adverse reproductive outcome. In particular, hypothyroidism and thyroid autoimmunity disorders have been shown to have both short- and long-term consequences on mother and child. An updated review is merited to revise many of the traditional views on thyroid disorders in pregnancy. RECENT FINDINGS: Thyroid disorders constitute the commonest group of pre-gestational endocrine disorders found in pregnant women. In mothers taking antithyroid medications, breastfeeding is considered safe. The relatively high prevalence of hypothyroidism, especially subclinical hypothyroidism, the significance of screening and treatment, and the roles of iodine insufficiency and thyroid antibodies on the outcome of pregnancy and long-term neurological development of the offspring have been documented. In hypothyroid women, the dose of thyroxine replacement often needs to be adjusted from as early as the first trimester to maintain an adequate circulating thyroxine concentration. SUMMARY: Apart from overt hyperthyroidism and hypothyroidism diagnosed before and during pregnancy, biochemical abnormalities or evidence of thyroid autoimmunity in clinically euthyroid women can affect both obstetric outcome and long-term neurological development of the offspring. Screening for thyroid function and autoimmunity, and timely and appropriate treatment, will improve pregnancy outcome. The thyroid function of infants born to mothers with thyroid disorders should also be assessed as serial monitoring and treatment may be necessary.     

Transplacental passage of anti-thyroid auto-antibodies in a pregnant woman with auto-immune thyroid disease.

We report the intra-uterine and postnatal thyroid status of a newborn, whose mother, affected with Hashimoto's thyroiditis superimposed on a previous Graves' disease, again became hyperthyroid during the third trimester of pregnancy. The mother had very high levels of anti-thyroid auto-antibodies, including TSH receptor auto-antibodies (TRAb) measured as TSH-binding inhibiting auto-antibodies (TBIAb). In order to exclude fetal thyroid dysfunction due to passive transplacental transfer of TRAb, fetal blood samples were obtained by cordocentesis at 21, 27 and 32 weeks of gestation. A transplacental transfer of TRAb was already seen at 21 weeks, but no alteration of fetal thyroid function was present at that time. In the following weeks, a rise in TRAb and circulating thyroid hormones was observed both in the fetus and mother, accompanied by overt hyperthyroidism in the mother and by growth retardation in the fetus. At birth, TRAb were shown to have stimulating activity both in the newborn and mother. This report documents the early transplacental passage of thyroid auto-antibodies and underlines the importance of close follow-up of pregnant women with auto-immune thyroid disorders.     

Latent polyglandular autoimmune syndrome type 2 case diagnosed during a shock manifestation

There are many types of polyglandular autoimmune syndrome (PAS). PAS type 2 is the most common type among adults. For PAS type 2 (PAS-2) diagnosis, detection of Addison's disease with autoimmune thyroid disease and/or type 1 diabetes mellitus are required. Premature ovarian insufficiency, pernicious anemia, vitiligo, alopecia, myasthenia gravis, celiac disease and autoimmune diabetes insipidus may be comorbidities of this condition. Contrary to the common belief, latent PAS is more common than the manifest forms. Here, we present a PAS-2 case diagnosed via adrenal crisis. At the time of diagnosis, the case was observed to have thyroid, adrenal and ovarian involvement. Therefore, PAS-2 and possible immunologic disorders were discussed.     

Thyroid disorders and pregnancy.

During pregnancy physiologic changes in thyroid function occur which should not be misinterpreted as pathological. Thyroid disorders may complicate pregnancy and need thorough investigation and treatment in order to ensure a favourable pregnancy outcome. The incidence of hyperthyroidism in pregnant women has been reported to be approximately 0.2%. The leading cause is Graves' disease. Treatment of hyperthyroidism includes antithyroid drugs or surgery to avoid adverse effects on the neonate such as prematurity, intrauterine growth retardation and fetal or neonatal thyrotoxicosis. Use of radioactive iodine is contraindicated. Hypothyroidism during pregnancy is associated with gestational hypertension and low birth weight. Women on thyroid replacement therapy before pregnancy may require an increase in dosage during pregnancy. Pregnant women with chronic autoimmune thyroiditis have a higher incidence of spontaneous miscarriage. Nodular disease demands meticulous investigation to rule out a toxic adenoma or malignancy. Surgery in the case of cancer can be postponed under certain circumstances. Within one year following delivery, about 5-10% of women may exhibit postpartum autoimmune thyroid dysfunction, which may result in hypothyroidism.     

Medical disorders in pregnancy, including hypertensive diseases

Medical disorders, including hypertensive diseases, may exist prior to pregnancy (eg, connective tissue diseases, chronic hypertension, thyroid disease) or may manifest themselves for the first time during pregnancy (eg, gestational diabetes, gestational hypertension). The outcome for a particular pregnancy will depend on the nature of the disease, the severity of the disease process at onset of pregnancy, and the quality of obstetric and medical management used. Management of pregnancies with preexisting medical disorders should begin before conception. These women should be evaluated to determine the severity of the disorder and to establish the presence of possible target organ damage. In addition, they should be counseled regarding the potential adverse effects of the disease on pregnancy outcome and the effects of pregnancy on their disease. These women should be instructed regarding the importance of early onset of prenatal care and compliance with frequent prenatal visits.     

Thyroid hormone receptors and reproduction

Thyroid disorders have a great impact on fertility in both sexes. Hyperthyroidism and hypothyroidism cause changes in sex hormone-binding globulin (SHBG), prolactin, gonadotropin-releasing hormone, and sex steroid serum levels. In females, thyroid hormones may also have a direct effect on oocytes, because it is known that specific binding sites for thyroxin are found on mouse and human oocytes. There is also an association between thyroid dysfunction in women and morbidity and outcome in pregnancy. In males, hyperthyroidism causes a reduction in sperm motility. The numbers of morphologically abnormal sperm are increased by hypothyroidism. When euthyroidism is restored, both abnormalities improve or normalize. In women, the alterations in fertility caused by thyroid disorders are more complex. Hyper- and hypothyroidism are the main thyroid diseases that have an adverse effect on female reproduction and cause menstrual disturbances--mainly hypomenorrhea and polymenorrhea in hyperthyroidism, and oligomenorrhea in hypothyroidism. In recent studies, it has become evident that it is not only changes in serum levels of SHBG and sex steroids that are responsible for these disorders, but also alterations in the metabolic pathway. Adequate levels of circulating thyroid hormones are of primary importance for normal reproductive function. This review presents an overview of the impact of thyroid disorders on reproduction.     

New‐Onset Graves’ Disease in the Postpartum Period

During routine evaluation for lactation failure, hyperthyroidism was discovered in a postpartum woman. Although postpartum thyroiditis and Hashimoto's disease are relatively more common than Graves’ disease during the postnatal period, this young woman was found to have new‐onset Graves’ disease. Distinguishing between normal postpartum symptoms and thyroid disorders can be challenging. Utilizing history, physical examination, and laboratory testing, the provider can identify the etiology of hyperthyroidism during the postpartum period. Treatment options differ depending on the cause of the thyroiditis and include antithyroid medications and beta‐blockers for relief of symptoms.     

Intrauterine growth of normal thyroid.

In this study we describe fetal thyroid growth during gestation and establish normal reference values using a simple linear ultrasound measurement of the thyroid. A total of 1180 normal singleton pregnancies, with no known risk factors for thyroid disorders, were enrolled from 12 to 39 weeks of gestation. The thyroid antero-posterior diameter was measured on a transverse axial plane through the fetal neck. The best fit regression was a power equation: thyroid diameter = 0.2412 weeks(1.0278) (r(2) = 0.55). The percentiles smoothed curves were calculated for each week. In conclusion, the results of the present study support previous findings that the fetal thyroid grows between 12 and 39 weeks of gestation with a steepest increase during the second trimester, that is when the fetal thyroid becomes functionally active. The normal ranges of this simple index of thyroid growth can be useful both as screening and for the clinical evaluation of pregnant patients with thyroid disorders.     

Endocrine causes of recurrent pregnancy loss

Objective: To review the available data on endocrine disorders and recurrent pregnancy loss. Findings: Our group found that most endocrine disorders do not seem to be correlated with a diagnosis of recurrent pregnancy loss (RPL). The exception to this is testing for thyroid stimulating hormone and thyroid antibodies, which is recommended due to a strong correlation with recurrent pregnancy loss and positive anti-thyroid peroxidase antibodies. Conclusion: The available literature supports testing thyroid function and antibodies in women with RPL. Testing for other endocrine disorders is only warranted if otherwise clinically indicated, independent from a history of recurrent pregnancy loss.     

Thyroid disease and other endocrine disorders in pregnancy

Endocrine disorders, in particular, thyroid disorders, are common in pregnancy. The endocrine adaptation to pregnancy, need for adequate iodine supplementation, and thyroxine replacement are presented. In addition, autoimmune diseases of the thyroid and pituitary that may occur subsequent to the immune changes of pregnancy and the postpartum period are discussed. A brief account of the presentation of other endocrine disorders (ie, pituitary,parathyroid, calcium, adrenal and gonadal disorders) also is given, along with their evaluation and management.