TSH Test: Purpose, Levels, Preparation & Price [2024]

TSH test is done to measure the level of thyroid-stimulating hormone (TSH) in the blood. Pituitary glands in our body produce TSH. This is important for the orderly function of the thyroid gland which in turn control many bodily functions. The test is helpful in studying the activity and effect of thyroid hormones in the body.

Test Details in Brief

Also Known As	TSH Test, TSH ultrasensitive, TSH
Purpose	Pregnancy, Tumors, Weight loss or gain, mood swing & general checkup
Preparation	As per the doctor recommendation
Fasting	Required in few cases, consult a doctor before the test
Reporting Time	8 to 24 Hrs.
Price	Rs. 200 to Rs. 400

Purpose of a TSH Test

A thyroid test or TSH test is done to measure the level of thyroid hormones and diagnose thyroid diseases. TSH level in our body helps in the diagnosis of the following: 

1. Hyperthyroidism (TSH above normal)- It is a condition when there is over production of thyroid hormones. The symptoms include loss of sleep, weight loss, puffy face etc.
2. Hypothyroidism (Below normal) is a condition when the thyroid gland secretes less hormones less than the normal. The symptoms include weight gain, fatigue, irregular periods etc.
3. Thyroiditis– it is swelling or inflammation of the thyroid gland. It might lead to over secretion or under secretion of thyroid hormones.
4. Thyroid tumors
5. Thyroid cancer
6. Other diseases like Grave and Hashimoto
7. Thyroid nodule

Thyroid test during pregnancy

It is essential for the development of the brain and nervous system of a baby during pregnancy. The baby uses the thyroid from the mother as the gland is underdeveloped in a baby in the womb.

Thyroid level increases during pregnancy. The pregnancy hormones, human chorionic gonadotropin (hCG) and estrogen increase the thyroid hormone in the blood. The TSH level might increase by 10-15% by the third trimester.  

Reference Range during pregnancy

Trimester	Unit	Reference range
1st trimester	uIU/ml	0.1-2.5
2nd trimester	uIU/ml	0.2-3.0
3rd trimester	uIU/ml	0.3-3.0

As a result, the reference range is lower for pregnant women. The abnormal level of TSH hormones than the reference range can cause problems such as-

• Premature birth
• Low birth weight baby
• Preeclampsia
• Congestive heart failure

Methods of TSH testing

There are 2 types of TSH testing.

Ultrasensitive 

TSH ultrasensitive test is a blood test that measures the level of thyroid-stimulating hormones (TSH) in the blood. The test is commonly used to find the root cause of fluctuation in the TSH levels.

TSH ultrasensitive test is important for the following reasons-

• It is used to diagnose hyperthyroidism and hypothyroidism
• As a screening test in a new born 
• Beneficial in monitoring hypothyroidism
• It is important to diagnose the cause of infertility in women. 

Uses of TSH ultrasensitive test

With the TSH ultrasensitive test hyperthyroidism can be treated at an early stage.

3^rd Generation TSH Test

Third generation thyroid-stimulating hormone test is the most sensitive screening test for hypothyroidism. The test shows a low level of thyroid hormones in the blood as a result of any deformity of the thyroid gland.

If the result is beyond the normal range there is a need to measure T4 (thyroxine) or FTI (free thyroxine index).

Pregnancy also influences the thyroid result. It is better to inform the healthcare provider about the pregnancy.

Preparation before TSH Test

In general, a TSH test does not require any prior preparation. However, the following should be kept in mind:

• Medicines: certain medication can interfere with the test result. Thus, you must inform the doctor about your existing medications.
• Thyroid medicine before test: If you are already taking medicines for a thyroid problem then you must skip the dose before getting yourself tested for thyroid-stimulating hormone (TSH). Always consult your doctor before skipping the medicines.
• During sickness: Acute health issues can interfere with the TSH test. One must get the TSH test done only after completely recovering from illness.
• Time of the day: TSH test depends on the time of the day. Thus, for monitoring of TSH level, it is preferable to give the sample at the same hour of the day. It reaches peak levels between 2 – 4 a.m. and at a minimum between 6-10 pm.

Procedure

TSH test requires a blood sample for testing. Thus the procedure entails the drawing of blood from the body. Common procedure is

• The test is performed by withdrawing a sample of blood from the vein in the arms. 
• The site of puncture is cleaned with antiseptic and a band is tied on the upper arm. This makes the vein swell with blood.
• Blood is withdrawn with a syringe, collected and sent to the lab.
• The band is removed and the site of the puncture is covered with a bandage.

Results of TSH Test

Thyroid testing usually includes the test for TSH, T3 and T4. Further, FT3 & FT4 may be required for better diagnosis.

• T3 and T4 hormones are secreted by thyroid stimulating hormone (TSH). 

• T3 (triiodothyronine) and FT3 (free triiodothyronine) is done to diagnose hyperthyroidism. 

• T4 (thyroxine) and FT4 (free thyroxine) test is done to diagnose hypothyroidism and hyperthyroidism.

TSH test results are used by doctors to diagnose thyroid disorders. The test result may be either of the following three.

Normal TSH Level

The normal range of the TSH depends upon age, gender and body weight. However, the normal range is as shown below

Test Name	Method	Unit	Normal Range
TSH, Serum	CLIA	uIU/ml	0.4-5.5

High level of TSH

A high level of thyroid hormones in the blood indicates an underactive thyroid gland. It is a condition when the thyroid gland produces a low level of hormones in the blood.

Symptoms include-

• Weight gain
• Swelling on the face and neck
• Dry skin
• Thin hair
• Depression
• Disturbance in menstrual cycle
• Intolerance to cold temperature
• Fatigue
• Fertility problems

Low level of TSH

Low TSH or low level of thyroid-stimulating hormone indicates overactive thyroid glands. In such situations the thyroid gland secrets high levels of hormones in the blood.

Symptoms of hyperthyroidism include-

• Weakness in the muscles
• Loss of weight 
• Difficulty in sleeping
• Diarrhea
• Mood swings
• Irregular heart beat
• Nervousness 

Sample report

You shall take a view of the sample report given below.

What to do after the TSH test

TSH test or thyroid-stimulating hormone test does not reveal the reason for abnormal thyroid function. As a result, the healthcare provider may ask for further diagnostic tests that may include-

• T4
• T3
• FT3
• FT4
• Anti-TPO test (Diagnose Grave’s or Hashimoto’s disease)

TSH Test price in India

TSH is an affordable test and its price usually ranges from Rs 200 to Rs 500. However, prices do tend to vary depending on lab and city. Thus, we have provided the prices in some of the popular labs and metro cities. However, you can visit bookmerilab.com to check prices at nearby diagnostic centres in your city.

Conclusion

Your doctor uses the TSH test to diagnose thyroid conditions such as hypothyroidism and hyperthyroidism. A high and low level of thyroid can disturb your routine life. Fluctuation of the hormones during pregnancy causes various pregnancy-related complications.

After getting the test done your doctor will interpret the result and provide you with more information.