Study of thyroid hormones in pregnancy

Madhu Juneja, Salil Barsode, Tushar Panchanadikar


Background: Thyroid disorder is often overlooked in pregnant women this is because of nonspecific symptoms and hyper metabolic state of normal pregnancy. To evaluate the thyroid function in pregnant women in all the three trimesters and to study their impact on pregnancy outcome.

Methods: A prospective study in 200 randomly selected antenatal cases was carried out during a period of two years in a tertiary care medical college in Western Maharashtra. A detailed general and systemic examination was carried out and Thyroid stimulating hormone (TSH) was done in all cases. Any case with an abnormal TSH level was further tested for T3 T4 levels.

Results: The mean TSH level was 1.6 µIU/l which was less than the standard cut off of 2.5 µIU/l. 61% had decreasing level of TSH with advanced gestation. An abnormal thyroid function was seen in 8.5% cases.

Conclusions: Standardization of TSH, T3, T4 is still a concern as it varies significantly in different studies. Estimation of TSH with T3 T4 could not be correlated during pregnancy with advancing gestational age. The real impact of hypo/hyperthyroidism on fetal outcome could not be statistically established.


Fetal outcome, Pregnancy, Thyroid hormones

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