Iodine deficiency in pregnant women at first trimester in Ankara

Iodine deficiency in pregnant woman in Ankara was shown in previous studies. We aimed to conduct a study in a tertiary center to investigate the need for iodine replacement in our population.

This was a single tertiary center, non-interventional, retrospective, cross-sectional study. Data were retrieved retrospectively from 440 women who were in the first trimester in gestational age. Maternal iodine status, thyroid-stimulating hormone (TSH) levels and T4 levels were examined. Urinary iodine concentration (UIC) was calculated based on the Sandell-Kolthoff reaction, which is a colorimetric method. We excluded patients with previous or current thyroid disease. Thyroid hormones and TSH were measured using chemiluminescence immunoassays.

Iodine deficiency prevalence (urinary iodine <150 μg/L) was 84.7% in first trimester of pregnancy in our population. The median UIC was 81.6 (1-450) μg/L, indicating iodine insufficiency. All the patients declared iodized salt use. None of the patients were taking iodine replacement. The mean TSH level was 1.53±1.27 mIU/L, (0.01 mIU/L-14.74 mIU/L) and the mean T4 level was 12.51±5.01 mIU/L (7.09 mIU/L-23.7 mIU/L). The TSH levels of 56 patients were higher than 2.5 mIU/L. According to these results, 12.72% of the patients had subclinical hypothyroidism based on serum TSH and free thyroxine levels. Isolated hypothyroxinemia was present in one patient.

Our study demonstrated that pregnant women still develop iodine deficiency in Ankara despite mandatory iodine salt use. Iodized salt use does not provide enough iodine supplement, especially in pregnant women. Iodine supplementation has been shown to enhance neurologic development and psychomotor performance. We suggest that iodine should be a part of routine laboratory evaluation at the first prenatal visit for its importance in early pregnancy. Also, iodized salt use education should be provided to women to eradicate iodine deficiency. Iodine supplements should be recommended to all pregnant women in addition to iodized salt.