TSH estimation as a screening test for thyroid disease in the First trimester of Pregnancy

Dr. Arsh Chowdhary; Dr. Neelesh Risbud; Dr. Prachi Bapat

Volume : IX, Issue : VI, June - 2020

TSH estimation as a screening test for thyroid disease in the First trimester of Pregnancy

Dr. Arsh Chowdhary, Dr. Neelesh Risbud, Dr. Prachi Bapat

Abstract :

While there is agreement that overt maternal hypothyroidism (serum thyroid stimulating hormone (TSH) >10 mIU/L) should be treated immediately; the evidence is mixed regarding the harm associated with subclinical hypothyroidism and the benefits of thyroxine replacement. The diagnosis of hypothyroidism rests on the recognition of an increased serum concentration of TSH which may be affected by many factors including gestational age, analytical method, the antibody status of the mother, ethnicity, iodine nutrition and even the time of day when the blood is collected. The 97.5th percentile of TSH at the end of the first trimester is commonly used as the upper boundary of normal in early pregnancy with a default value of 2.5 mIU/L specified in a number of recent clinical guidelines.