Hypothyroidism in Pregnancy
What is hypothyroidism?
Hypothyroidism is a condition where the level of thyroid hormones in your blood is lower than normal. This occurs when the thyroid gland makes too little or no thyroid hormone. The thyroid gland is a butterfly-shaped organ that is located in the front part of your neck. The thyroid hormones are special chemicals that maintain and control how the body uses the energy it needs. These include keeping a normal body temperature, heart rate, growth, and weight.
What causes hypothyroidism?
The following conditions may cause or increase your risk of having hypothyroidism:
Autoimmune:
The immune system is the part of your body that fights infection. A problem with the immune system may make your body attack even its own cells. Hashimoto's disease is the most common autoimmune disease that may cause hypothyroidism.
Diet:
Having too little or no iodine in your diet. Iodine is an important mineral used by the thyroid gland to work correctly and make thyroid hormones.
Family history:
Having a family member with hypothyroidism or autoimmune disease may increase your risk.
Medicines:
Taking certain medicines, such as those used to treat high blood pressure or depression, may cause hypothyroidism. Medicines to treat hyperthyroidism (too much thyroid hormone) may also decrease the thyroid hormones in your body.
Treatments:
Radiation therapy used to treat cancers of the head and neck can destroy your thyroid gland. Surgery done to remove all or part of the thyroid gland may make you more likely to develop hypothyroidism.
Other diseases or conditions:
Having thyroid problems, such as goiter (enlarged thyroid) or thyroiditis (swelling of the thyroid). Nodules (lumps) caused by infections or cancer may grow in your thyroid gland and affect how it works.
What happens with hypothyroidism during pregnancy?
During pregnancy, there is an increased need of the thyroid hormone and iodine in the body. This increased need may not be met and may cause serious health problems. Pregnancy also makes your body, including the thyroid gland, work harder for both you and your growing baby. The health of women who get pregnant while having this condition may become worse. A past history of hypothyroidism or other thyroid problems may increase your chance of having it again during pregnancy. Having this condition while you are pregnant may put you at risk for any of the following:
Abortion (miscarriage).
Babies with birth defects or low birth weight.
Heart failure.
Preterm labor. This means that the baby is born earlier than the due date.
Pre-eclampsia. This is when you have hypertension (increased blood pressure), low platelet count, protein in the urine, and problems thinking.
Stillbirths or babies dying inside the womb.
What are the signs and symptoms of hypothyroidism during pregnancy?
During pregnancy many changes happen to your body. The signs and symptoms of hypothyroidism may start slowly and you may not notice any changes. You may only feel that something is wrong when signs and symptoms worsen. Early signs and symptoms include:
Body weakness and fatigue (feeling more tired than usual).
Dry, flaky skin, and thin, brittle fingernails and hair.
Feeling depressed, irritable, and anxious.
Feeling too cold when the temperature is just right or normal for everyone else.
Muscle pain.
Later signs and symptoms include:
Constipation (dry, hard bowel movements).
Enlarged thyroid gland.
Hoarseness, or a change in your voice or speech.
Sleepiness and problems thinking clearly, such as being forgetful and easily confused.
Swelling around the eyes.
Too much and too sudden weight gain.
Very slow heartbeat and trouble breathing.
How is hypothyroidism diagnosed?
Your caregiver may ask you about your family history, and do a physical exam. He will also do tests to check on your unborn baby. You may have any of the following:
Blood tests:
Blood is taken to learn how well your thyroid is working. These tests may tell your caregiver how low your thyroid hormone levels are in your blood. This information may also be used to see how well any treatments are working.
Fetal ultrasound:
This simple test uses sound waves to show pictures of your baby (fetus) inside your uterus. Jelly-like lotion is spread on your abdomen, and a small handle is gently moved through the lotion. As this is done, pictures of your baby can be seen on a TV-like screen. Caregivers can learn the age of your baby and see how fast he is growing. The movement, heart rate, and position of your baby can also be seen. Caregivers can see your placenta, and can tell if you have more than one baby.
How is hypothyroidism treated?
Treatment for hypothyroidism will depend on your age, health, pregnancy, and the level of your thyroid hormones. Thyroid medicines are given to replace and raise your thyroid hormone levels back to normal. If another disease or condition has caused your hypothyroidism, it will also be treated. Medicine may be given to decrease the symptoms of hypothyroidism. Ask your caregiver if you need to increase the amount of iodine in your diet during your pregnancy. Iodine is found in milk, fish, clams, and other seafood. Also ask him if you need to take a mineral and vitamin supplement (pill) that contains iodine.
Where can I find more information?
Having hypothyroidism during pregnancy may be hard for you and your baby. You and those close to you may feel angry, sad, or frightened. These feelings are normal. Talk to your caregivers, family, or friends about your feelings. Contact the following for more information:
American Thyroid Association
6066 Leesburg Pike, Suite 550
Falls Church, VA 22041
703-998-8890
800-849-7643
www.thyroid.org
The Hormone Foundation
8401 Connecticut Ave.
Suite 900Chevy Chase, MD 20815-5817
USA800-467-6663
www.hormone.org
Endocrine and Metabolic Diseases Information Service
National Institutes of Health
6 Information Way
Bethesda, MD 208923569
888-828-0904
http://www.endocrine.niddk.nih.gov
