Iodine status in healthy pregnant women in Korea: a first report.
OBJECTIVE
Proper iodine intake is important during pregnancy for both fetal neurodevelopment and maternal thyroid function. Korea is known as a high iodine intake area. However, there are no data regarding iodine status in pregnant Korean women. Therefore, we evaluated the iodine status of pregnant women in Korea by measuring urine iodine concentration.


METHODS
This study had an observational, prospective design. We enrolled 344 healthy pregnant women who visited Samsung Medical Center in Korea for a routine antenatal checkup between April 2012 and September 2013. We measured iodine and creatinine concentration (Cr) in spot urine samples and TSH level in serum at the time of enrollment.


RESULTS
The median urinary iodine concentration (UIC) and UIC adjusted by Cr were 427.3 μg/L and 447.9 μg/gCr, respectively. There was no difference in median UIC according to trimester of pregnancy (P value = 0.953). Serum TSH level was not different according to UIC level when subjects were grouped according to WHO iodine recommendations (P value = 0.401).


CONCLUSIONS
The median UIC of healthy pregnant women in Korea was 427.3 μg/L and 447.9 μg/gCr, which are more than adequate according to WHO criteria. Considering the wide range of UIC, we recommend active education about adequate iodine intake during pregnancy in areas where iodine intake is more than adequate according to WHO criteria.
Division of Endocrinology and Metabolism, Department of Medicine, Thyroid Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Irwon-dong, Gangnam-gu, Seoul, 135-710, Republic of Korea.
Yoon Young
YY
Cho
Division of Endocrinology and Metabolism, Department of Medicine, Thyroid Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Irwon-dong, Gangnam-gu, Seoul, 135-710, Republic of Korea.|Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Soonchunhyang University, Seoul, Republic of Korea.
Hye Jeong
HJ
Kim
Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Irwon-dong, Gangnam-gu, Seoul, 135-710, Republic of Korea.
Soo-Young
SY
Oh
Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Irwon-dong, Gangnam-gu, Seoul, 135-710, Republic of Korea.
Suk-Joo
SJ
Choi
Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Soo-Youn
SY
Lee
Division of Endocrinology and Metabolism, Department of Medicine, Thyroid Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Irwon-dong, Gangnam-gu, Seoul, 135-710, Republic of Korea.
Ji Young
JY
Joung
Division of Endocrinology and Metabolism, Department of Medicine, Thyroid Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Irwon-dong, Gangnam-gu, Seoul, 135-710, Republic of Korea.
Dae Joon
DJ
Jeong
Division of Endocrinology and Metabolism, Department of Medicine, Thyroid Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Irwon-dong, Gangnam-gu, Seoul, 135-710, Republic of Korea.
Seo Young
SY
Sohn
Division of Endocrinology and Metabolism, Department of Medicine, Thyroid Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Irwon-dong, Gangnam-gu, Seoul, 135-710, Republic of Korea.
Jae Hoon
JH
Chung
Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Irwon-dong, Gangnam-gu, Seoul, 135-710, Republic of Korea. crroh@skku.edu.
Cheong-Rae
CR
Roh
Division of Endocrinology and Metabolism, Department of Medicine, Thyroid Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Irwon-dong, Gangnam-gu, Seoul, 135-710, Republic of Korea. swkimmd@skku.edu.
Sun Wook
SW
Kim
D000328:Adult; D015992:Body Mass Index; D001835:Body Weight; D003404:Creatinine / Q000652:urine; D005260:Female; D006801:Humans; D007455:Iodine / Q000008:administration & dosage / Q000652:urine*; D009752:Nutritional Status; D011247:Pregnancy; D011264:Pregnancy Trimesters; D011446:Prospective Studies; D056910:Republic of Korea; D013972:Thyrotropin / Q000097:blood
D013972:Thyrotropin; D007455:Iodine; D003404:Creatinine
Iodine; Korea; Pregnancy; Urine; Women