Study to Assess Iodine Status in Pregnant Women

Pregnancy is associated with substantial changes in thyroid physiology and represents a major stress on maternal iodine homeostasis leading to an increased requirement of iodine. The fetus is particularly vulnerable and maternal iodine deficiency can cause irreversible cognitive and motor deficits.

The main objective of the present study was to assess the iodine status of pregnant women and to know the prevalence of iodine deficiency in them.

A Cross-sectional, observational, hospital based study was done in normal, healthy pregnant women. Pregnant women, who were in their first (n=60) and third (n=60) trimesters were selected. Age matched healthy non pregnant women served as control group (n=60). Urine Iodine Concentration (UIC) and Serum Thyroid Stimulating Hormone (TSH) levels were determined. The cut off values for iodine nutrition sufficiency as defined by WHO/UNICEF/ICCIDD guidelines were used.

The results obtained showed that the values of Urine Iodine Concentration in third trimester pregnant women were significantly less (P<0.05) compared to first trimester women. Increased hormonal and metabolic demands may lead to depletion of total body iodine stores which if not compensated by adequate dietary iodine intake is reflected by decreasing levels of UIC with increase in gestational period. The serum TSH values in third trimester pregnant women were significantly high (P<0.05) compared to first trimester and non pregnant women reflecting increased thyroidal stimulation. The study also documented the negative correlation between maternal TSH and UIC.

The findings of the present study indicates that Pregnant women tend to become more iodine deficient as pregnancy advances. So, monitoring of iodine nutrition status during pregnancy is essential, to plan and evaluate adequate interventions either in the form of specific dietary care or therapeutic iodine supplementation.