TSH

TSH in Pregnancy

The normal level of TSH in pregnancy is < 3.0 mU/L. During pregnancy, thyroid gland activity is markedly increased due to increased demand for thyroid hormones to carry out a healthy pregnancy with no risk for preterm delivery or miscarriage, and even for the mother’s well-being.

Implications of low TSH levels

When the thyroid-stimulating hormone is low, this signifies hyperactivity of the thyroid gland, referred to as hyperthyroidism. In hyperthyroidism, the thyroid gland excessively produces thyroid hormones which will constantly send negative feedback to reduce TSH release from the pituitary gland.Many common conditions cause the thyroid gland to become overactive like Grave’s disease, inflammation of the gland itself, multimodal Goiter, or an adenoma growing. Sometimes it happens when hypothyroidism treatment is too harsh, requiring a dose reduction to be resolved. In less common cases, the excess of thyroid hormones is secondary to a tumor in the thyroid gland.Low TSH symptoms comprise weight loss, anxiety, tremors, tachycardia, bulging of the eyes, poor sleeping hygiene, hirsutism, menstruation disturbances, more frequent bowel activity, and enlarged thyroid gland upon palpation.If left untreated for a long time, hypothyroidism may cause heart problems like arrhythmias and atrial fibrillations which can have detrimental effects on health. It may also lead to osteoporosis, loss of vision, or even a thyrotoxic crisis which is a life-threatening emergency.

Treatment of low TSH

To bring back normal TSH levels, different modalities may be employed depending on the patient’s age, concomitant conditions, and tolerability. This includes conventional oral medication, radiation, or surgery.

– Oral medication aims to target the thyroid and to relieve symptoms associated with hyperthyroidism. There are three antithyroid medications: Methimazole/Topazole, Carbimazole, and Propylthiouracil, and all directly halt the thyroid hormones production, leading to a boost in TSH secretion.

– They follow a daily regimen with a dose that will depend on the severity of the condition and will be maintained after reaching normal levels. Beta-blockers are added to antithyroid therapy to alleviate symptoms such as tachycardia and tremors.

– Another option is radioactive iodine therapy or ablation. The radioactivity from the orally administered iodine will directly destroy thyroid gland cells so fewer thyroid hormones are produced. It takes up to 18 weeks to reach full effectiveness, and sometimes therapy may require another course

– Surgery is a definitive cure for hyperthyroidism, reserved for patients who fail or cannot antithyroid and radioactive iodine therapies, and in those whose thyroid gland is too enlarged with a suspected malign tumor.

LH levels can sometimes fluctuate outside the normal range and will either decrease or increase, each having different causes and implications depending on the gender. Testing for LH level is done in concordance with FSH levels by drawing blood samples with lab kits. The test is ordered when the physician needs to investigate the reason behind irregular menstruation, inability to conceive, delayed or early puberty, or change in libido.

When the thyroid-stimulating hormone is high, this indicates an under-activity of the thyroid gland, referred to as hypothyroidism. In hypothyroidism there are not enough thyroid hormones being produced by their gland, leading to excess production of TSH since the concentrations are not enough to trigger the negative feedback to the pituitary gland.

Hypothyroidism is the result of different disorders and conditions such as autoimmune diseases like Hashimoto’s disease, congenital hypothyroidism, damage to the thyroid gland due to chemotherapy or inflammation, or surgical removal of the thyroid gland for other underlying reasons. Hypothyroidism can sometimes be the result of hyperthyroidism treatment, in that case, treatment should be revised.

While a TSH level of more than 5.0 mU/L is considered abnormal, there is no consensus on what is considered a dangerously high TSH level due to differences in ranges both from a patient’s side and the institution’s standard. But naturally, an extremely high TSH reading will require a more rigorous and longer treatment.

High TSH levels symptoms include lethargy and fatigue, hoarseness, weight gain, feeling cold, hair loss, dry skin, constipation, irregular menstruation sometimes infertility, and bradycardia.