Thyroid status of normal pregnant women in Dhaka City

The thyroid gland secretes thyroid hormones having important role in embryogenesis and fetal development during pregnancy. The present study was carried out to find out alteration in the thyroid size and serum thyroid hormonal levels (T4, T3 and TSH) in normal pregnant women as compared to non-pregnant women in Dhaka City. For this purpose, thirty-five pregnant women during third trimester attending OPD Dhaka Medical College Hospital from January 1998 to July 1998 were selected randomly and twenty-one non-pregnant women of childbearing age group were selected as control. The study revealed a high prevalence of goiter in both pregnant (34.2%) and non-pregnant women (28.5%). The study showed that the serum TT4 level of non-pregnant women was normal (mean +/- SD = 113 +/- 23 nmol/L) and the serum TT4 of pregnant mother during third trimester was significantly higher (mean +/- SD = 200 +/- 63 nmol/L, P < 0.001) compared to that of non-pregnant women. The serum TT3, levels of both pregnant and non-pregnant women were within normal range without significant difference between them. It was found that the serum TSH level of pregnant mother was within normal limit and was closely similar to that of non-pregnant women showing no significant difference between them. It can be concluded from the study that although goiter was present in a considerable number of pregnant women but they were euthyroid status as observed by increased production of serum total thyroxin (TT4) by thyroid to fulfill the maternal requirement, with nearly unchanged TT3 and TSH secretion.