Normal Range of TSH and FT4 in Pregnancy in Thrace Region of Turkey
Normal Range of TSH and FT4 in Pregnancy in Thrace Region of Turkey
Physiological changes necessitate the use of pregnancy-specific reference ranges for
 thyrotrophin (TSH) and free T4 (FT4) to diagnose thyroid dysfunction during pregnancy.
 Although many centers use fixed upper limits for TSH of 2.5 or 3.0 mU/L, this may lead to
 overdiagnosis or even overtreatment.

 The new guidelines of the American Thyroid Association have considerably changed
 recommendations regarding thyroid function reference ranges in pregnancy accordingly. Any
 hospital or physician that is still using the 2.5 or 3.0 mU/l cut-off for TSH during
 pregnancy should evaluate their own lab-specific cut-offs.

 The investigator's objective is to establish a rational reference range of serum TSH for the
 diagnosis of subclinical hypothyroidism in the first, second, and third trimester of pregnant
 women in the Thrace region in Turkey.
Serum thyroid function tests (including T3, T4, TSH, Anti-TPO) will be obtained from the
 singleton pregnancies in the first, second, and third trimester to determine the local
 specific normal ranges.
Inclusion Criteria:

 -  Singleton pregnancy

 -  Twin pregnancy

 -  Free of pre-existing thyroid disease

 -  That do not use thyroid interfering medication

 -  That did not undergo IVF treatment

 -  TPOAb negative

 Exclusion Criteria:

 -  Adolescent pregnancy

 -  Patient with pre-existing thyroid disease

 -  TPOAb positive

 -  Patient using thyroid interfering medication

 -  That had IVF treatment