The overall aim of the present project is to investigate if intake of cod in pregnancy has impact on infant development up to 12 month. 142 pregnant women will be allocated into two groups, one counsuming cod two times the week for four months and one group will continue to follow their habitual diet. To study this, urine samples, dietary data and blood samples from the mother and from the infant, as well as data on neurodevelopment and cognitive functioning will be collected at several time points.

The World Health Organization considers iodine deficiency to be "the single most important preventable cause of brain damage" worldwide. The effect of severe iodine deficiency is well documented. Pregnant and nursing mothers have increased requirements and are thus a vulnerable group. Iodine is a key component of thyroid hormones that are critical for normal development of the brain and nervous system in utero. There is little data on the effect of mild- and moderate iodine deficiency. Results from the Norwegian Mother and Child cohort (n = about 62,000) shows that only 22% of the participants had an iodine intake, estimated from food frequency questionnaire, that meets the recommendations of WHO / UNICEF / ICCIDD. Urine samples from a sub-sample (n = 119) confirmed suboptimal iodine status. The results are consistent with recent data from a NIFES study of about 100 women from the municipality of Fjell, which reviled suboptimal iodine status both in pregnancy and three months after birth. Preliminary results from the study Little in Norway, where NIFES measured the iodine status in approximately 1,000 pregnant from across the country, is also consistent with these investigations. Dairy products is highlighted as the main source of iodine for the participants in the Norwegian Mother and Child cohort, while lean fish is the food group that has the highest Iodine levels. In this article, the positive effect of seafood was explained by the fatty acids EPA and DHA, while the latest publication suggests that the effect of an adequate intake of seafood during pregnancy are more complex, and that the high iodine levels in seafood may also be important. Based on this knowledge, there is a need for an intervention study where pregnant consume cod regularly over a longer period and where the children are followed up over time. Thus, in the present project the researchers will investigate if intake of cod in pregnancy has impact on infant development up to 12 month. 142 pregnant women will be allocated into two groups, one consuming cod two times the week for four months and one group will eat as normal. Urine samples, dietary data and blood samples from the mother and from the infant, as well as data on neurodevelopment and cognitive functioning will be collected at several time points.

Inclusion Criteria:

• ≤ gestational week 19,
• prim parous,
• singleton pregnancy,
• Norwegian speaking and / or understand Norwegian writing due to all validated tests of the child will be in Norwegian.

Exclusion Criteria:

• allergies to fish,
• chronic diseases known to affect iodine status (Graves' disease, Thyroiditis, Thyroid Nodules, known hypothyroidism, known hyperthyroidism).