Agriculture Reference
In-Depth Information
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o D i in e
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u P P L e m e n t a t i o n
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t u D i e s
Peru
Children of mothers from three iodine-deficient villages in Peru supplemented in preg-
nancy had higher developmental levels compared with unsupplemented controls from
the same villages (Pretell et al. 1972). However, the difference was not significant.
ecuador
Pregnant women in one iodine-deficient village in Ecuador were treated with iodized
oil either during months 4 to 7 of pregnancy (group 1) or before conception (group
2). Compared with control children from an untreated village, children in group 2
had higher IQ scores, but there were no differences between group 1 and controls
(Ramirez et al. 1969). In a second study, a greater percentage of children of mothers
treated before the sixth month of pregnancy had normal developmental levels than
was the case in children of untreated mothers (Ramirez et al. 1972).
zaire
Pregnant women in an area of severe iodine deficiency in Zaire were randomized
to either iodized oil or a vitamin placebo on average at the 28th week of pregnancy
(Thilly et al. 1980). Infants of treated mothers had significantly higher developmen-
tal levels than infants of placebo-treated mothers.
Papua new guinea
In a double-blind randomized controlled trial in 16 villages in Papua New Guinea,
iodine treatment in pregnancy led to a significant reduction in cretinism (Pharoah
et al. 1971). Children in 5 of the villages were followed up in later studies. Children
whose mothers received iodized oil had better cognitive and fine motor skills than
control children (Connolly et al. 1979).
china
Treatment in China was given to pregnant women, infants, and children aged 1 to 3
years. Scores of the 1- to 3-year-old children prior to treatment were used as control
values. At age 2 years, children whose mothers received iodine during the first or
second trimester of pregnancy had higher developmental scores than the controls
(Cao et al. 1994). In another trial, children whose mothers received iodine in early
pregnancy (first and second trimester) had higher psychomotor scores compared with
a group who received iodine later in pregnancy or with children who first received
iodine at age 2 years. Later in childhood, there was also a trend of better cognitive
performance in those who received iodine before the third trimester (O'Donnell et
al. 2002).
These studies provided strong evidence of the impact of iodine deficiency, partic-
ularly during pregnancy, on children's development. Improvements in iodine status
in school-aged children may also benefit cognitive ability (van den Briel et al. 2000).
There is a clear need to strengthen efforts to prevent iodine deficiency in mothers
and children.
