Survey of Urinary Iodine of Pregnant Women in Different Periods of Pregnancy

Objective To study the levels of urinary iodine of pregnant women in different periods of pregnancy.Methods Based on the severity of iodine deficiency in Guizhou,mild,moderate and severe counties in iodine deficiency disorders(IDD) areas were selected with a stratified random sampling method.The pregnant women in early(n=57),middle(n=57) and late period(n=113) of pregnancy were randomly selected by a certain percentage from each IDD area.The urine sample of 30 ml was collected randomly from each pregnant woman for the determination of urinary iodine concentration(UIC) with As3 +-Ce4 + catalytic spectrophotometry(WS/T 107-2006).Results The medians of urinary iodine were 289.4,265.8 and 219.2 μg/L for women in early,middle and late period of pregnancy,which had achieved the range of the standard of WHO,but the percentage of urinary iodine of lower than 150 μg/L increased with the gestational period,and it could reach to 28.3% for women in late period of pregnancy.Conclusion Iodine deficiency in degrees has been found in a part of pregnant women in gestational periods in the present study,so more attention should be paid to the iodine nutrition in the pregnant women not only in the late period of pregnancy but also in the early period.