Screening for thyroid disorders in pregnancy with TSH estimation

Jayanthy Thammiah


Background: Thyroid dysfunction is the second common endocrine disorder seen in pregnancy. There are various physiological changes in pregnancy which lead to alterations in thyroxin levels. Hypothyroidism and hyperthyroidism can have effect on pregnancy and fetus. In India there are no guidelines for screening for thyroid disorders in pregnancy. This study was performed to detect thyroid disorders in asymptomatic pregnant women, to treat them early and compare the outcome with normal pregnancies. To evaluate TSH estimation as screening test.

Methods: It was a prospective study done at Kempegowda Institute of Medical Sciences Bangalore. 400 asymptomatic pregnant women with singleton pregnancy irrespective of age, gestational age, parity and socioeconomic status were included. Multiple pregnancy and those on treatment for thyroid disorder were excluded. Written informed consent obtained. At first visit detailed history and examination was done .Apart from routine investigations estimation of TSH was done. When the TSH levels were abnormal FT4 and anti TPO antibody was estimated.

Results: The incidence of thyroid dysfunction was 12%. The association of risk factors was higher in the screen positive patients which was 28(58.3%) as compared to 44(12.5%) in Euthyroid patients, P <0.001. Maternal complications were more (65.2%) & Premature births 26.1% in patients with thyroid disorders compared to normal women (25.6%) and Premature births 6.92% , P = 0.009 .

Conclusions: Screening all pregnant women with TSH for thyroid dysfunction especially those with previous adverse pregnancy outcome is useful. Early diagnosis and treatment will definitely improve the pregnancy outcome.


Thyroid disorders, TSH, Maternal outcome, Fetal outcome, Hypothyroid, Hyperthyroid, Euthyroid

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