Urinary iodine excretion in pregnancy: a pilot study in the region of Nepal

Pregnancy is accompanied by profound alterations in the thyroid economy and the relative iodine deficiency. The median Urinary Iodine Excretion (UIE) is the most reliable indicator of the population's iodine nutrition. The physiological alterations in normal pregnancy, such as an increased glomerular filtration rate, potentially invalidate UIE as an assessment tool in pregnancy.

To assess the Urinary Iodine Excretion (UIE) in pregnant mothers and to enquire about the current status of their iodised salt intake.

We carried out a cross-sectional study in which urine samples were collected from 45 pregnant mothers who were admitted to the antenatal ward. The iodine level in the urine was analysed by a method which was provided by Singh and Ali, to determine the Urinary Iodine Excretion (UIE). A questionnaire was introduced to document the status of the dietary intake of iodised salt. The UIE was expressed in median (interquartile) and the other data are expressed in frequency and percentage. Fisher Exact test was applied to compare between UIE and iodine intake.

Thirteen (28.88%) pregnant mothers had UIEs of <150 μg/L, which were below the cut-off point of the UIE for pregnant mothers. Overall, 33 mothers were from the Terai region; among them, one third had UIEs of <150 μg/L. Among the 45 pregnant women, 15 (33.34%) were not using iodised salt and the rest were using iodised salt. Among those who were using iodised salt (30 out of 45), 8 pregnant women had UIEs of <150 μg/L and among those who were not using iodised salt, 5 pregnant women had UIEs of < 150 μg/L.

The UIE was below 150μg/L in a substantial percentage (28.89%) of pregnant women of the Terai region, regardless of their intake of iodised salt.