Prenatal Iron Supplements: Safety and Efficacy in Tanzania (MAL1)

The purpose of this study is to determine safety and efficacy of prenatal iron supplementation in an area of high malaria burden among women who are not anemic or iron deficient.

Iron deficiency anemia and malaria are urgent public health problems in sub-Saharan Africa, including Tanzania. There is a paucity of good quality randomized trials assessing the safety and efficacy of iron supplementation in pregnancy, and its effects on perinatal health outcomes. Prenatal iron supplementation is recommended based on its demonstrated benefit in preventing and treating maternal anemia. There is limited data on the efficacy of iron supplementation on pregnancy outcomes, including birth weight. There are also concerns regarding the use of iron supplementation, particularly among non-anemic women. In particular, there is a lack of research on the safety and efficacy of prenatal iron supplementation in developing regions, characterized by extensive burden of iron deficiency, malaria, and other endemic infectious diseases. Evidence from randomized controlled trials is urgently needed to examine the safety and efficacy of iron supplements among pregnant women in malaria endemic regions, particularly among women who are not anemic. NOTE: The time frames listed for the maternal malaria and hemoglobin outcomes were updated on 4/22/15. This record initially indicated that maternal malaria anemia and hemoglobin would be measured at several specific time points throughout the study. Instead, maternal malaria was measured throughout pregnancy and hemoglobin was measured only at delivery. Due to an oversight, we did not update this record when this protocol change took effect at the start of the study.

Placental infection status will be categorized as infected if there are asexual parasites in the placenta blood; not infected if the placental blood smear is negative; or status unknown if no placental smear is available.

Placental malaria parasite density will be defined as number of parasites per μL of blood or 200 white blood cells; the latter will be converted to a count per μL of blood assuming a count of 8000 WBC/μL.

Maternal malaria will be defined as fever within the last 72 hours with any parasitemia on a peripheral blood smear.

Anemia will be defined as hemoglobin less than 11 g/dl. Severe anemia will be defined as less than 8.5 g/dl.

Inclusion Criteria: at or before 27 weeks of gestation primigravida or secundigravidae not anemic (defined as Hb<8.5 g/dL) not iron deficient (defined as serum ferritin <12 μg/L) HIV-uninfected intend to stay in Dar es Salaam until delivery and for at least six weeks thereafter. Exclusion Criteria: After 27 weeks gestation not primigravida or secundigravidae anemic iron deficient HIV-infected High iron stores at baseline (i.e., serum ferritin >200 μg/L) do not intend to stay in Dar es Salaam until delivery and for at least six weeks thereafter.

Abioye AI, Hughes MD, Sudfeld CR, Premji Z, Aboud S, Hamer DH, Roberts DJ, Duggan CP, Fawzi WW. The effect of iron supplementation on maternal iron deficiency anemia does not differ by baseline anemia type among Tanzanian pregnant women without severe iron deficiency anemia. Eur J Nutr. 2023 Mar;62(2):987-1001. doi: 10.1007/s00394-022-03029-0. Epub 2022 Nov 8.

Yang J, Wang M, Tobias DK, Rich-Edwards JW, Darling AM, Abioye AI, Pembe AB, Madzorera I, Fawzi WW. Gestational weight gain during the second and third trimesters and adverse pregnancy outcomes, results from a prospective pregnancy cohort in urban Tanzania. Reprod Health. 2022 Jun 16;19(1):140. doi: 10.1186/s12978-022-01441-7.

Yang J, Wang D, Darling AM, Liu E, Perumal N, Fawzi WW, Wang M. Methodological approaches to imputing early-pregnancy weight based on weight measures collected during pregnancy. BMC Med Res Methodol. 2021 Feb 5;21(1):24. doi: 10.1186/s12874-021-01210-3.

Etheredge AJ, Premji Z, Gunaratna NS, Abioye AI, Aboud S, Duggan C, Mongi R, Meloney L, Spiegelman D, Roberts D, Hamer DH, Fawzi WW. Iron Supplementation in Iron-Replete and Nonanemic Pregnant Women in Tanzania: A Randomized Clinical Trial. JAMA Pediatr. 2015 Oct;169(10):947-55. doi: 10.1001/jamapediatrics.2015.1480.