Pregnancy and Hyperthyroidism: How does thyroid increase during pregnancy?

The thyroid is a butterfly-shaped gland located at the front of your neck.

Thyroid hormones are crucial for the proper development of your baby’s brain and nervous system. Because, for the first 3 months of pregnancy, the thyroid hormones produced by your body are supplied to your baby through the placenta. When your pregnancy reaches the second trimester, your baby’s thyroid glands start producing thyroid hormones, but in insufficient quantities. Therefore, the thyroid hormones produced in your body remain essential until your pregnancy reaches 18-20 weeks.

This is why, if a woman experiences hyperthyroidism during pregnancy, it can be hard to diagnose.

Generally, the primary cause of hyperthyroidism during pregnancy is Graves' Disease. Graves' Disease is an autoimmune disorder in which your body produces Thyroid Stimulating Immunoglobulin (TSI). TSI is a type of antibody that increases the production of thyroid hormones.

In some cases, severe nausea and vomiting leading to weight loss and dehydration, known as hyperemesis gravidarum, can also cause hyperthyroidism during pregnancy.

During hyperemesis gravidarum, the level of HCG hormones increases, which in turn raises thyroid hormone levels.

This problem usually resolves within 6 months of pregnancy.

Some common symptoms of hyperthyroidism during pregnancy include:

• Increased heart rate
• Feeling excessively hot
• Extreme fatigue
• Trembling hands
• Weight loss
• Or lack of weight gain during pregnancy.

If you notice any of these symptoms, you should consult your doctor.

Source:- 1.https://www.niddk.nih.gov/health-information/endocrine-diseases/pregnancy-thyroid-disease 

                2. https://www.hopkinsmedicine.org/health/conditions-and-diseases/staying-healthy-during-pregnancy/hypothyroidism-and-pregnancy