Abstract
Objective: To evaluate the impact of a mandatory bread fortification programme on estimated iodine intakes of childbearing women and to describe the extent to which uptake of a maternal iodine supplement recommendation is associated with sociodemographic characteristics.
Design: A postpartum survey was conducted using a self-administered questionnaire. Details on pre- and post-conceptional supplement use, bread intake, iodized salt use and maternal sociodemographic and obstetric characteristics were obtained.
Setting: Eleven maternity wards and hospitals located across New Zealand.
Subjects: Seven hundred and twenty-three postpartum New Zealand women.
Results: Mean iodine intake from fortified bread was 37 μg/d prior to conception. Younger women, women with higher parity, single women and those with unplanned pregnancies were less likely to meet the pregnancy Estimated Average Requirement (EAR) for iodine (all P ≤ 0·022). Although not statistically significant for all months of pregnancy, women with less education and income were less likely to meet the EAR (P ≤ 0·11 and P ≤ 0·2 for all months, respectively) and indigenous Māori women and Pacific women were less likely than New Zealand Europeans to meet the EAR (P ≤ 0·17 and P ≤ 0·051 for all months, respectively). During pregnancy, iodine-containing supplement uptake at the recommended level (150 μg/d) was non-uniform across sociodemographic subgroups, with the most disadvantaged women benefiting the least from this public health policy.
Conclusions: The disparities in supplement uptake noted here highlight the need for prioritizing further efforts towards universal salt iodization, such as the mandatory fortification of additional processed foods with iodized salt.