Iodine deficiency disorder among pregnant women in a tertiary care hospital of Kolkata, India.

The present unicentric, hospital based, non-interventional, cross-sectional study was undertaken to assess the iodine status of pregnant women attending the antenatal clinic at a medical college in Kolkata, India, during the different trimesters of pregnancy and to compare their iodine status with those of age-matched non-pregnant control women. Assessment of the iodine status was based on urinary iodine excretion (UIE). Serum levels of free triiodithyronine (fT3), free thyroxine (fT4) and thyroid stimulating hormone (TSH) were assayed as an indirect measure of iodine status. A statistical comparison between the median values for UIE, TSH, fT4 and fT3 in pregnant women and non-pregnant controls revealed a significant difference between the median values for UIE (p < 0.0047), TSH (p < 0.00001) and fT4 (p < 0.001). UIE and fT4 were significantly lower and TSH was significantly higher in pregnant women than in non-pregnant controls. However, no significant difference in median values for fT3 concentration between the groups was seen (p = 0.4). Only 4 cases out of 200 pregnant women had an UIE of less than the lower cut-off value for UIE recommended by the WHO corresponding to optimal iodine intake. The results indicate most pregnant subjects attending the antenatal clinic at Medical College Kolkata, India, a tertiary care institution, did not suffer from significant iodine depletion. This may be ascribed to increased awareness of this condition and the accessibility of iodized salt among the study population.