8046 Milk Provision as a Potential Intervention to Improve Iodine Status in a Pregnant Cohort in Northern Ireland (NI), UK: A Randomised Controlled Trial

Abstract Disclosure: L.R. Kayes: None. K.R. Mullan: None. J.V. Woodside: None. Iodine deficiency is the leading cause of reversible mental retardation worldwide. During pregnancy there is ∼50% increase in iodine requirement for foetal neurodevelopment. The most recently studied cohorts of pregnant women across Ireland and UK consistently demonstrated mild iodine deficiency (target median urinary iodine concentration (mUIC) ≥150 µg/L). A recent study in NI has shown that women of child-bearing age provided with three litres of cow’s milk per week had improved iodine status. We wished to explore whether a similar milk intervention might improve iodine status during pregnancy. Pregnant women were recruited at their first antenatal appointment, and all were provided with the British Dietetic Association’s iodine food fact sheet. Participants were randomised to either milk intervention, (four litres/week milk delivered weekly free of charge), or no milk delivery (control group). Patients were stratified based on use of an iodine-containing multivitamin prior to randomisation. Urine was collected at recruitment, after 12-week intervention period, in the third trimester and 6-12 weeks postnatally along with an infant urine sample when possible. A total of 55 urine samples were collected from infants. A total of 118 women were recruited. Participants had a mean age of 32 years, (range 21 - 45) with a mean BMI of 27.5 kg/m2. Mean gestational age was 12 weeks (IQR 12-13 weeks). The mUIC in the whole group women was 53.2 µg/L in the first trimester. In the control group the mUIC at the first study visit (n=59) was 93.4 µg/L (22% achieving iodine sufficiency); at the second visit (n=38), the mUIC was 158.7 µg/L with 34% achieving sufficiency. In the milk group the mUIC at the first study visit (n=59) was 82.0 µg/L with 10% achieving sufficiency (no statistical significance between groups, p=0.08); at the second visit (n=43), mUIC was 154.7 µg/L with 37% achieving sufficiency (no statistical difference between groups p=0.78). The mean change in UIC between the first and second trimesters was 44.5 and 88.1 µg/L in the control and milk arms respectively (p=0.27). In this cohort, 71.4% of women reported taking an iodine-containing multivitamin in the first trimester of pregnancy with no difference between group randomised to milk intervention (p=0.95). In the infants, mUIC was 124.1 µg/L with no statistically difference in the proportion reaching iodine sufficiency according to maternal randomisation (p=0.64) or maternal use of an iodine-containing multivitamin (p=0.95). In this cohort, there was no significant improvement in mUIC in those receiving a milk intervention. Presentation: 6/1/2024