This study revealed that the iodine knowledge of pregnants in Turkey is insufficient. Despite the implementation of a national salt iodization program in the past 20 years, iodine knowledge and habits of pregnants were not previously determined. To our knowledge, this is the first study assessing the iodine knowledge of pregnants in Turkey. Several studies performed in New Zealand, the UK, Australia, and Norway also found that pregnants had little knowledge of iodine [10, 12, 16, 17]. It was detected that the participants had difficulty in defining the most important dietary sources of iodine. In this study, fish and seafood were stated as the best iodine source in the diet, similar to other studies [13, 18]. Some studies reported as the best source of dietary iodine [13, 16, 18]. However, iodophors are not applied to milk containers and milk doesn't contain iodine in Turkey. Therefore, it was found that Turkish pregnants have less knowledge about milk as a source of dietary iodine.
In the Norwegian study, 41.0% of pregnant women stated that iodized salt is one of the most important sources of iodine in the diet [10]. However, in this study, the majority of pregnant women (77.3%) reported table salt as one of the best dietary iodine sources. It is compulsory to iodize the table salt and label the package in Turkey. The knowledge difference between the two countries can be explained by table salt regulations. The permissible limit to iodize table salt in Turkey is 25–40 mg/kg potassium iodate, which can affect the iodine intake of those who use this salt. Even though only 42% of the participants knew the mandatory iodine regulations, probably most of the population consider the “iodized table salt” as an extra commercial specification of table salt brands.
In the present study, more than half of pregnant women (68.0%) stated that iodine deficiency would cause serious problems. On the other hand, it was found that they could not correctly relate the diseases with deficiency. Another study evaluated 520 childbearing-age women in the UK and Ireland and reported that almost half (41.0%) of the participants did not know or accurately identify any health problems associated with iodine deficiency [13]. Studies among women of childbearing age in New Zealand, the UK and Australia also showed low awareness of iodine deficiency as a public health problem [16–18]. This study was carried out in Trabzon, where is known to be an endemic goiter area of Turkey. Therefore, the higher knowledge of the participants about iodine deficiency-related diseases can be explained by the social interactions of the participants to have some friends or relatives suffering from one of these diseases.
This study found out that the mean iodine knowledge score of participants was low. In addition, there was no significant difference between iodine knowledge scores according to age, trimester and previous pregnancy (p > 0.05). O’Kane et al. (2016) reported that young women (18–25) had higher iodine knowledge levels [13]. In a study conducted by Charlton et al. (2012) with pregnant and lactating women, there was no significant difference between iodine-related knowledge scores during pregnancy and lactation [6]. Previously in a qualitative study, it was determined that pregnants in Norway receive very little information about nutrition in antenatal care. It was reported that pregnants usually receive basic educations towards the end of their pregnancy. [19]. Similarly, it was observed that the women participating in the “Pregnancy School Project” at the state hospitals in Turkey are mostly in the second trimester of their pregnancies and are more willing to get information about nutrition. In this study, it was found that pregnants who received education about nutrition had higher iodine knowledge scores. However, half of the pregnants (50.3%) stated that they had never received any nutritional education before. Studies in Australia, New Zealand, and the UK and Norway also reported a lack of knowledge about iodine during pregnancy [12, 13, 20]. Also, other studies indicated that pregnants were more sensitive about nutrition than non-pregnant women. [21, 22]. In this study, the iodine knowledge scores of the pregnants in the first trimester were lower than the other trimesters. As previously mentioned, the health professionals providing prenatal care to women in Turkey are encouraged to provide general information about a healthy diet. In previous studies conducted in different regions of Turkey, the pregnants were found to have insufficient iodine intake during pregnancy [8, 23, 24]. However, although pregnants are at risk of inadequate iodine intake, there is currently no public education initiative to improve the situation. It is determined that better education is associated with higher iodine knowledge scores during pregnancy. Hence, it is suggested that pregnants should be given specific education about iodine starting from the pre-pregnancy period.
Although pregnancy education is important to improve the knowledge about iodine, the general education level of the women should be considered, as well. This study found that as the education level of the participants increased, mean iodine knowledge scores were also increased (p < .05). The studies conducted in Norway, the United Kingdom and Sri Lanka revealed similar results and participants with higher education levels were found to have higher iodine knowledge scores [13, 20, 25]. Contrary to these results, in a study conducted by Lucas et al. in Australia, it was reported that education level did not affect iodine knowledge score [20].
This study had some limitations. Firstly, as it was a cross-sectional study and the results may not be generalizable for all pregnant women. Since the research area is an endemic goiter region, iodine awareness may be higher than in the rest of the country. Besides, that would be more inclusive to perform a study not only with pregnants, also including women who are breastfeeding and in childbearing age. As being a pioneer study in the research area, further studies in different regions and larger populations will provide more knowledge about the situation in the whole country. Despite the limitations, this study can be considered as an anchor in the literature to compare the development of awareness in Turkey.