TSH levels are inversely proportional to thyroid hormone levels. Abnormal fluctuations in TSH levels during first trimester of pregnancy can lead to serious health complications. Read on….
The anterior pituitary gland releases TSH, thyroid stimulating hormone to stimulate the thyroid. Thus TSH triggers the release of thyroid hormones T3 and T4. If the thyroid becomes overactive (the condition is known as hyperthyroidism), the pituitary gland releases less TSH, as there is no need to stimulate the thyroid. On the contrary, in case of an under-active thyroid (the condition is known as hypothyroidism), the pituitary gland releases more TSH to activate the thyroid. Thus, TSH levels vary according to the thyroid activity.
TSH Levels During Pregnancy
- First Trimester: 0.24 – 2.99 mIU/L
- Second Trimester: 0.46 – 2.95 mIU/L
- Third Trimester: 0.43 – 2.78 mIU/L
To know more about the TSH levels in normal men and women, browse through TSH levels chart.
TSH Levels During First Trimester of Pregnancy
Women with hypothyroidism may notice elevated TSH levels, while women with hyperthyroidism may have abnormally low TSH during pregnancy. Both these conditions are considered as serious, as they can result in serious health complications. So mothers with thyroid disorders need to take extra care during pregnancy.
Hypothyroidism
The autoimmune disease Hashimoto’s thyroiditis can result in hypothyroidism. When the body’s own immune system considers the thyroid gland as a foreign body and attacks the thyroid, it is called autoimmune disease and the condition is known as Hashimoto’s thyroiditis. Thyroid gets inflamed and its ability to produce hormones gets impaired. Mothers with Hashimoto’s thyroiditis are likely to give birth to babies with birth defects.
Under-treated hypothyroidism increases the risk of having child with learning disabilities and even stillbirth. So, women with hypothyroidism need to increase their usual thyroid hormone intake (drug like levothyroxine) on confirmation of pregnancy. They should consult their health care provider immediately and should get the dose adjusted according to the body’s needs. During pregnancy, demand for thyroid hormone increases as the body has to take care of both, the mother and the fetus.
Taking iron and calcium supplements, or fortified products along with thyroid hormone should be avoided, as they can affect thyroid drug’s effectiveness. Hypothyroidism or high TSH levels increases the risk of miscarriage, premature birth or high blood pressure at the time of delivery, leading to serious complications. Symptoms like increased sensitivity to cold, muscle cramps, excessive tiredness, excessive weight gain, dry and pale skin, constipation can be noticed during hypothyroidism.
Hyperthyroidism
Usually, mothers suffering from Grave’s disease (an autoimmune disease) would be diagnosed with hyperthyroidism and low TSH levels during the first trimester. Symptoms like increased heart rate, nervousness, heat intolerance, increased irritability, tremors, profuse sweating and fatigue might be noticed by the pregnant woman. A low dose of antithyroid dose (drug like propylthiouracil) helps lower the symptoms of Grave’s disease.
Pregnant women should avoid excessive intake of iodized salt, seafood (as it is rich in iodine), sea salt or processed foods that are rich in iodine. Excessive intake of caffeine can also have an adverse effect on pregnancy, and so should be avoided. Application of ice packs and following relaxation techniques like meditation, breathing techniques like pranayama can help in easing hyperthyroidism symptoms like nervousness, heat intolerance or palpitations.
Women who are planning to get pregnant should consult an endocrinologist and obstetrician, if they have thyroid problems. Women diagnosed with thyroid disorders should check the thyroid hormone levels and TSH levels during first trimester, regularly. Women with undiagnosed, uncontrolled, or improperly treated thyroid problems usually experience severe nausea, vomiting, fatigue, and depression during first trimester. Thyroid dysfunction increases the risk of intrauterine growth retardation, miscarriage, pre-term labor, stillbirth and even mental retardation in the child.