Thyroid-stimulating hormone parameters and screening for congenital primary hypothyroidism

Abstract

Background: Screening for primary congenital hypothyroidism is performed in more than 80 countries around the world, with 1 in 2000-4000 live births. Objective: To early diagnose the primary congenital hypothyroidism and prevent form the disability of children. Methods: During the 7-year period from 2013 to 2020, 22616 infants born in Maternity hospitals and the National Center for Maternal and Child Health in Ulaanbaatar were randomly selected for the current study. Thyroid hormones were tested for plasma in the presence of a positive thyroid-stimulating hormone threshold of 20 IU/ml. Results: Screening for congenital primary hypothyroidism in 22616 infants identified 11 children with congenital primary hypothyroidism. Sixty-seven children were tested positive for thyroid-stimulating hormone, and 11 children with congenital primary hypothyroidism and 10 children with transient hypothyroidism were tested positive, and 46 cases had false-positive results. During the same period, 10.3% of live births in the capital city were involved. The survey call rate was 0.03%. Conclusions: In Ulaanbaatar, primary congenital hypothyroidism occurs in 1 in 2056 live births. Thyroid-stimulating hormones are elevated at low gestational age and low birth weight. Taking the test within the first 30 hours after birth and taking the wrong blood sample is the main reason for false positive results.