Grant: Doctoral Research Award: Canada Graduate Scholarships

Pregnancy is a vulnerable time for nutrient deficiencies because of the increased demands of a growing baby. In Canada, prenatal supplements contain iron commonly in the form of iron salts which are poorly absorbed resulting in excess unabsorbed iron in the gut. This is associated with gastrointestinal side effects such as nausea and constipation and also increases susceptibility to pathogen growth. These side effects are especially a concern during pregnancy, as the associated elevated inflammation may further impair iron absorption. An alternative formulation, called ferrous bisglycinate, is more readily absorbed in the cells lining the intestine and has been shown to be as effective as standard iron salts at improving iron status even when administered at a lower dose. Previous studies of iron supplementation in pregnancy, however, have focused only on indicators of maternal iron and anemia status. The provision of prenatal supplements is important not only for maternal health but also to ensure adequacy of critical nutrients delivered to the baby to prevent risk of long-term physical and psychological impairments associated with micronutrient deficiencies. We propose a trial that will additionally assess iron stores in the baby using umbilical cord and placental iron measures. We will also broaden the assessment of tolerance to iron supplementation through quantifying gut pathogen abundance in addition to occurrence of adverse events reported in current literature. We will recruit pregnant women 20-25 weeks' gestation aged 19-42 years from the greater Vancouver area, who will be randomized to receive either standard iron or ferrous bisglycinate in daily prenatal supplements. This research will provide guidance to inform policy regarding optimal iron form and dose in prenatal supplements from both an efficacy and safety lens for both mother and baby in Canada and globally.