Endocrinology - Nutritional Disorders

Endocrinology is that branch of medicine that diagnoses and treats hormonal conditions. Hormones play a central role in conceiving and carrying a pregnancy to term. Fertility issues can have hormonal causes. Similarly, maintaining a normal weight, as well as tight blood glucose control are essential to enhance pregnancy rates. Working with your diabetes doctor to make lifestyle changes is vital.

The thyroid gland is an endocrine gland responsible for regulating metabolism and other essential functions of the body. The thyroid gland functions undergo transformations during pregnancy, as a natural consequence of physiological and hormonal changes. The endocrinologist shall have to interpret the medical test results diverging from reference values, taking into account the background of pregnancy.

In the instance of an endocrine dysfunction, the woman may find herself unable to conceive. Disorders of the thyroid gland can cause a series of imbalances in the body. The endocrinologist guidance is paramount in restoring hormonal balance and creating an environment conducive to pregnancy.

Dysfunctions of the thyroid gland can be either hypothyroidism or hyperthyroidism. These may be pre-existing conditions that can negatively impact the pregnancy development, or occur by reason of it. These conditions can be autoimmune in nature and require close collaboration between the obstetrician and the endocrinologist.

Hypothyroidism is one of the main causes of female infertility. It is an endocrine disorder characterized by an insufficient production of thyroid hormones, which have an important role in regulating metabolism and the reproductive function. Hypothyroidism can affect fertility through several mechanisms, such as menstrual disorders, anovulation, hyperprolactinemia, or altered oocyte quality. Therefore, it is important to detect and treat hypothyroidism when you want to get pregnant. In order to diagnose the condition as a cause of infertility, the following investigations are required:

• Determining the level of thyroid-stimulating hormone (TSH) – this is a blood test that measures the amount of TSH secreted by the pituitary to stimulate the thyroid.
• Determining the level of free thyroid hormones (FT4 and FT3) – these are blood tests that measure the amount of thyroid hormones available for action at cellular level.
• Prolactin level determination (PRL) – this is a blood test that measures the amount of PRL secreted by the pituitary.
• Thyroid ultrasound – this is an imaging investigation that allows visualization of the structure and size of the thyroid, as well as possible nodules or cysts. Thyroid ultrasound can reveal any abnormalities in the gland.

In order for the fetus to properly develop its brain and nervous system, as well as to preserve harmony between mother and baby, an adequate amount of thyroid hormones is required. Hypothyroidism can cause the following issues during pregnancy:

• Miscarriage – the risk of miscarriage is increased in women with untreated hypothyroidism, especially in the first trimester of pregnancy. This is because excess thyroid hormones can affect the implantation of the embryo and cause an increase in prostaglandin levels, which can stimulate uterine contractions and lead to the expulsion of the product of conception.
• Preeclampsia –is a serious complication of pregnancy, characterized by increased blood pressure and the presence of protein in the urine after week 20 of pregnancy. Preeclampsia can affect both mother and fetus, causing edema, convulsions, kidney failure, coagulopathy, intrauterine growth retardation or fetal death. Hypothyroidism can promote preeclampsia by increasing heart rate, decreasing peripheral vascular resistance and altering endothelial function.
• Preterm birth – is defined as the birth occurring before week 37 of pregnancy. Premature birth can have negative consequences on the fetus, such as breathing difficulties, brain hemorrhage, infections or neurological sequelae. Hypothyroidism can cause premature birth by affecting the placenta or triggering preterm labor.
• Postpartum hemorrhage – is excessive blood loss after childbirth, which can endanger the mother’s life. Hypothyroidism may increase the risk of postpartum hemorrhage by rising uterine contractility or through clotting disorders.
• Congestive heart failure – is an impairment of the heart function, which involves accumulation of fluid in the lungs and other tissues of the body. Hypothyroidism can trigger congestive heart failure by increasing heart rate, decreasing peripheral vascular resistance, and altering the systolic function.

Hypothyroidism in pregnancy can have various manifestations and mimic the usual symptoms of pregnancy or depression. Here are some of the symptoms:

• Fatigue – a state of physical and mental weakness, which does not get better with rest. Expecting women with hypothyroidism may feel more exhausted than normal, even if they get enough sleep. Fatigue can affect the ability to manage daily activities.
• Cold intolerance – a high sensitivity to low temperatures, which causes chills, tremors or a freezing sensation. Pregnant women with hypothyroidism may perceive the environment colder, even if the temperature is adequate. Cold intolerance can affect the comfort and well-being of a pregnant woman.
• Weight gain – an excessive accumulation of body fat, which is not only due to the growth of the fetus. Expecting women with hypothyroidism may gain more weight than it is normal during pregnancy, even if they have a balanced diet and an adequate caloric intake. Weight gain can affect a pregnant woman’s health and self-image.
• Constipation – difficulty passing stools, which causes abdominal discomfort, bloating or pain. Childbearing women with hypothyroidism may experience constipation more frequently, even if they have an adequate fiber and fluids intake. Constipation can affect the quality of life and promote hemorrhoids.
• Dry skin – this is the dehydration of the superficial layer of skin, which causes a feeling of roughness, itching or cracking. Pregnant women with hypothyroidism may experience dry skin, even if they use moisturizers or oils.
• Friable hair and nails – this involves changes in the structure and strength of hair and nails, which cause hair loss, breakage of nails or the appearance of striations on their surface.

Hypothyroidism can have various causes, which can tell on both the thyroid gland and the pituitary gland or fetus. Among the most common causes are:

• Iodine deficiency – this is a common cause of hypothyroidism. Iodine is an essential element for the synthesis of thyroid hormones. During pregnancy, the need for iodine increases, as the fetus takes the mother’s reserves of iodine and thyroid hormones for its development. When iodine intake is insufficient, both mother and fetus may suffer from hypothyroidism.
• Autoimmune thyroiditis – this is a common condition in developed countries, especially in women with a family history of autoimmune thyroiditis or other autoimmune disorders. The disease is a chronic inflammation of the thyroid gland, triggered by an attack of the immune system on thyroid cells. This leads to progressive destruction of the thyroid and decreased production of thyroid hormones. Autoimmune thyroiditis can be triggered or aggravated by pregnancy.
• Disorders of the pituitary gland – these are rare causes of hypothyroidism, involving a dysfunction of the pituitary gland, located at the base of the brain. The pituitary gland produces the thyroid-stimulating hormone (TSH), which tells the thyroid how many hormones to produce. If the pituitary gland does not produce enough TSH or produces an abnormal TSH, the thyroid does not function properly and secretes fewer thyroid hormones. Disorders of the pituitary gland can be caused by tumors, radiation, surgery or autoimmune diseases.
• Congenital hypothyroidism – this is a rare cause of hypothyroidism in newborns, which can be genetically transmitted or can be triggered by environmental factors. Congenital hypothyroidism involves the absence, malformation or dysfunction of the thyroid gland in the fetus. This leads to a decrease in thyroid hormone levels in fetuses and newborns, with serious repercussion on the physical and mental development of the baby. Congenital hypothyroidism can be caused by the mother’s iodine deficiency during pregnancy, exposure to ionizing radiation, infectious or autoimmune diseases of the mother, or the negative impact of certain drugs or chemicals on the fetus.

Hyperthyroidism is the excess of thyroid hormones. The most serious consequence of this disorder is pre-eclampsia.

Here are some of the most common symptoms of hyperthyroidism:

• Heat intolerance – a decreased sensitivity to high temperatures, which induces excessive sweating, thirst or thermal discomfort.
• Fatigue – a state of persistent, chronic physical and mental weakness.
• Anxiety – a state of unease, worry or exaggerated fear that has no objective cause. Anxiety can affect your well-being and relationship with your partner or child. 
• Tachycardia – an increase in heart rate above 100 beats per minute, which is not explained by physical exertion or strong emotions. Women with hyperthyroidism may experience tachycardia more often than usual, even if they’re not performing strenuous activities or aren’t stressed. Tachycardia can affect cardiovascular health and increase the risk of heart complications.
• Nausea and severe vomiting – persistent nausea and severe vomiting, even in the absence of heavy or spoiled foods intake. The expectant woman may have nutrition and hydration problems because of severe nausea and vomiting, which can be a sign of a serious toxicosis called hyperemesis gravidarum.
• Weight loss – a reduction in body mass, which is not solely due to loss of water or adipose tissue. Women with hyperthyroidism may lose more weight than normal during pregnancy, even if they have a normal or even increased appetite. Weight loss can affect fetal health and development.

Hyperthyroidism can have various causes, which affect both the thyroid gland and the pituitary gland or fetus. Here are some of the most common causes:

• Graves’ disease – an autoimmune disease, in which the immune system attacks the thyroid gland and causes it to produce more thyroid hormones than needed. It is the most common cause of hyperthyroidism in pregnancy, especially in young women or women with a family history of the disease. Graves’ disease can be triggered or aggravated by pregnancy.
• Gestational hyperthyroidism – a mild and temporary form of hyperthyroidism that occurs in some women in the first trimester of pregnancy. It is caused by increased levels of pregnancy hormones, such as estrogen and human chorionic gonadotropin (hCG), which stimulate thyroid hormone production. It usually does not require treatment and resolves spontaneously after birth.
• Thyroiditis – an inflammation of the thyroid gland, which can have infectious, autoimmune or postpartum causes. Thyroiditis can cause an initial phase of hyperthyroidism, followed by a phase of hypothyroidism.

The endocrinologist shall prescribe the appropriate treatment during pregnancy. However, the treatment shall be adapted to the nature of the condition, namely whether it is a pre-existing condition or a condition developed during pregnancy.

A healthy diet and a normal weight are beneficial both for conceiving and for the healthy development of the fetus. Patients can benefit from consultation with the specialist in diabetes and nutritional disorders, in order to establish a nutrition plan appropriate to each case.