The thyroid gland (thyroid gland), other endocrine glands, together with the nervous and immune systems, coordinates and regulates the activity of all other body systems, making it possible to adequately respond to the constantly changing conditions of the external and internal environment. Studies have shown that thyroid dysfunction occurs more often in women and especially in reproductive age. The resulting functional changes in the thyroid gland (hypo- and hyperthyroidism) adversely affect the course of pregnancy. Inadequate treatment of maternal hypothyroidism can lead to various kinds of pregnancy complications: anemia, preeclampsia, placental abruption, postpartum hemorrhage and impaired cardiovascular function. With thyrotoxicosis during pregnancy, there is a risk of miscarriage, low fetal weight, and malformations .
The literature provides evidence that pregnancy causes an exacerbation of thyroid autoimmune diseases; so-called gestational thyrotoxicosis and gestational hypothyroidism can occur during pregnancy, which adversely affect pregnancy.
The aim of the study was to identify thyroid dysfunction in pregnant women with increased thyroid gland in the early stages of pregnancy, follow-up and correction of the revealed disorders, and develop tactics for managing pregnant women with thyroid dysfunction.
Material and Methods
A comprehensive study of 32 pregnant women with thyroid enlargement at the age of 27-42 was carried out. In 11 pregnant women, autoimmune thyroiditis (AT) was detected before pregnancy, in 10 – during pregnancy, 11 patients showed an increase in thyroid gland without dysfunction. The control group consisted of 12 healthy pregnant women.
To establish and confirm the diagnosis of autoimmune thyroiditis, ultrasound examination of the thyroid gland, determination of the titer of antibodies to thyroglobulin and microsomal fraction were performed. Thyroid status was assessed by determining the basal levels of thyroid (TG) and thyroid-stimulating hormones (TSH), as well as by clinical examination methods: study of the anamnesis, examination and palpation of the thyroid gland, assessment of clinical symptoms. Out of 21 pregnant women with AT, hypothyroid stage was observed in 13, hyperthyroid – in 8.
Heredity was studied by autoimmune endocrine diseases, gynecological and obstetric history. All studies were carried out in I, II, III trimesters of pregnancy. Thyroid status and titer of antibodies to thyroglobulin and microsomal fraction were assessed on the 5-6th day after birth in mothers and on the 5-6th day of life of the newborn. Ultrasound examination was performed using the ALOKA apparatus. Antibodies to thyroglobulin and microsomal fraction were determined using commercial kits for enzyme-linked immunosorbent assay produced by BIOTECHNO of the medical company “MULTINEST” (Moscow, Russia). Antibodies to thyroglobulin and microsomal fraction were determined using the ATP and ATG-ELISA-M kit. The results obtained were processed according to the generally accepted criteria of statistical variation analysis.
Results
Of 32 pregnant women with an enlarged thyroid gland, 21 patients were diagnosed with AT with hyper- and hypofunction, in 11 – an enlarged thyroid gland without dysfunction. In women with AT, heredity was studied: thyroid dysfunction was detected in 9 mothers of the examined patients, in 12 grandmothers, in 3 female relatives. In 8 patients, relatives were ill: type 1 diabetes mellitus (2 cases), type 2 diabetes mellitus (5), polyarthritis (1). In 11 patients, AT was detected before pregnancy; they received treatment at their place of residence for 1-5 years. When pregnancy occurred, women independently stopped treatment. In 10 women, AT was diagnosed during a real pregnancy, but it could have existed earlier, without symptoms.
The results of the study of the gynecological and obstetric anamnesis in all examined patients showed that 5 women suffered from secondary infertility (2-5 years), 4 women had an anamnesis of antenatal fetal death, 17 had early miscarriages, and 3 had late miscarriages. gestational age. On clinical examination, 11 pregnant women showed a diffuse increase in the thyroid gland II-III degree, while the gland was soft and elastic. Ultrasound of the thyroid gland showed an increase in its size and volume, the structure was not changed; hormonal and clinical indicators indicated euthyroidism. In 21 patients, the thyroid gland on palpation was dense, tuberous: grade II increase was noted in 2 women, grade II-III – in 18 women, grade III-IV – in 1 patient. Thyroid ultrasound revealed signs of AT. When comparing the ultrasound data of the thyroid gland in the dynamics of pregnancy (I and III trimesters), changes in its structure were not found.
Symptoms of hypothyroidism were noted in 13 patients, hyperthyroidism – in 8. The subjects were divided into groups: group 1 – pregnant women with an enlarged thyroid gland without dysfunction (n = 11), group 2 – pregnant women with AT and hypothyroidism (n = 13), group 3 – pregnant women with AT and hyperthyroidism (n = 8).
In the 1st group of women without AT with euthyroid enlargement of the thyroid gland, hormonal parameters did not differ from those in the control group, increased titers of antibodies to thyroglobulin and microsomal fraction were not found in all trimesters of pregnancy. In the 2nd group of pregnant women with AT and hypothyroidism, the TG indicators in the first trimester were statistically significantly reduced compared to the control; the TSH level was statistically significantly increased. The titer of antibodies to TG and microsomal fraction was increased compared to the control and had a tendency to decrease during treatment in the course of pregnancy. In the 3rd group of pregnant women with AT and hyperthyroidism, there was a significant increase in the level of TG in the first trimester of pregnancy, a decrease in the level of TSH compared with the control. The treatment led to the normalization of the parameters of TG and TSH, already in the II and III trimesters of pregnancy they did not differ from the control.
All pregnant women with AT were treated with thyroid drugs (L-thyroxine, thyrocomb, thyrotome, triiodothyronine) according to an individually selected scheme. In the case of the hyperthyroid form, AT was prescribed (b-blockers, valerian preparations. Pregnancy in the surveyed women proceeded smoothly, childbirth took place on time and without complications.
Discussion of the results
As the studies have shown, in pregnant women with an enlarged thyroid gland, thyroid dysfunction was revealed in 65.6% of cases; hypofunction of the thyroid gland – in 40.6% and hyperfunction – in 25%, laboratory and instrumentally confirmed AT.
Early diagnosis and adequate treatment led to an improvement in the general condition, disappearance of complaints and clinical manifestations of thyroid dysfunction, as well as normalization of the thyroid status, a decrease in the titer of antibodies to thyroglobulin and microsomal fraction. At the same time, no positive dynamics was noted with ultrasound in the dynamics of pregnancy and treatment. The existing literature data [8, 13] indicate that the state of immune suppression during pregnancy contributes to both the exacerbation of the existing autoimmune thyroid diseases and their occurrence. The authors note that in women with a genetic predisposition to autoimmune thyroid pathology, pregnancy is a factor provoking dysfunction [4, 8].
Our studies suggest that AT itself does not harm reproductive function, but a change in the functional state of the thyroid gland due to AT may have an adverse effect on the development of the fetus and the course of pregnancy. The existing burdened obstetric anamnesis in our patients (miscarriages, undeveloped pregnancy, antenatal fetal death) suggest the role of thyroid dysfunction in the genesis of obstetric pathology.
Correction of the thyroid status and its maintenance at a normal level during pregnancy contributed to the normalization of the functional state of the thyroid gland and, possibly, had a positive effect on the course of pregnancy and delivery.
Based on this study, we recommend that all pregnant women with an enlarged thyroid gland study the functional thyroid gland (thyroid status); women with dense, lumpy gland after ultrasound are shown to determine the titer of antibodies to thyroglobulin and microsomal fraction. The detection in the blood of these women of an increased titer of antibodies to thyroglobulin and the microsomal fraction indicates the possible development of gestational hypo-hyperthyroidism, as well as postpartum thyroiditis. Thus, early diagnosis and correction of thyroid dysfunction during pregnancy will help prevent complications of pregnancy and prevent the development of pathology in offspring.
Conclusions
1. Pregnant women with enlarged thyroid gland are recommended to examine thyroid function: thyroid status, thyroid ultrasound and, if indicated, titers of antibodies to thyroglobulin and microsomal fraction.
2. Increased titers of antibodies to thyroglobulin and microsomal fraction may be a risk factor for the occurrence of gestational thyroid dysfunction, postpartum thyroiditis.
3. Early diagnosis and correction of thyroid dysfunction in early pregnancy contribute to the normalization of the thyroid status, a decrease in antibodies, which may have a beneficial effect on the course of pregnancy.