Prenatal Iron Supplementation Reduces Maternal Anemia, Iron Deficiency, and Iron Deficiency Anemia in a Randomized Clinical Trial in Rural China, but Iron Deficiency Remains Widespread in Mothers and Neonates.
Study Goal
The researchers aimed to assess the effects of prenatal iron-folate supplementation on maternal and neonatal iron status, focusing on reducing iron deficiency (ID), iron deficiency anemia (IDA), and improving neonatal iron status.
Results Summary
Prenatal iron supplementation significantly reduced maternal anemia, ID, and IDA, with higher hemoglobin levels in the iron group. However, most women and over 45% of neonates still had ID, regardless of supplementation, though cord serum ferritin increased with higher maternal iron intake.
Population
Pregnant women (≤20 weeks gestation, aged ≥18 years, hemoglobin ≥100 g/L) in rural China with uncomplicated singleton pregnancies.
Effective Dosage
300 mg ferrous sulfate + 0.40 mg folate daily.
Duration
From enrollment (≤20 weeks gestation) until birth.
Interactions
None mentioned.
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
prenatal iron-folate supplementation | neutral | maternal and neonatal iron status | women with uncomplicated singleton pregnancies at ≤20 wk gestation, aged ≥18 y, and with hemoglobin ≥100 g/L | - | assess effects | #1 |
daily iron (300 mg ferrous sulfate) + 0.40 mg folate | increase | maternal hemoglobin | women at or near term | +5.56 g/L | was significantly higher | #2 |
iron supplementation | decrease | anemia risk | pregnant women | RR: 0.53; 95% CI: 0.43, 0.66 | reduced | #3 |
iron supplementation | decrease | risks of ID | pregnant women | RR: 0.74; 95% CI: 0.69, 0.79 by SF; RR: 0.65; 95% CI: 0.59, 0.71 by BI | reduced | #4 |
iron supplementation | decrease | risks of IDA | pregnant women | RR: 0.49; 95% CI: 0.38, 0.62 by SF; RR: 0.51; 95% CI: 0.40, 0.65 by BI | reduced | #5 |
iron supplementation | no change | ID | most women | 66.8% by SF, 54.7% by BI | had | #6 |
iron supplementation | no change | adverse effects | women | all minor | were similar | #7 |
iron supplementation | no change | cord blood iron measures | neonates | - | were no differences | #8 |
iron supplementation | no change | ID | neonates | >45% | had | #9 |
maternal iron capsules | increase | cord SF | neonates | β per 10 capsules = 2.60, P < 0.05 | showed higher | #10 |
prenatal iron supplementation | decrease | anemia, ID, and IDA | pregnant women in rural China | - | reduced | #11 |
iron supplementation | no change | ID | most women and >45% of neonates | - | had | #12 |
BACKGROUND: Previous trials of prenatal iron supplementation had limited measures of maternal or neonatal iron status. OBJECTIVE: The purpose was to assess effects of prenatal iron-folate supplementation on maternal and neonatal iron status. METHODS: Enrollment occurred June 2009 through December 2011 in Hebei, China. Women with uncomplicated singleton pregnancies at ≤20 wk gestation, aged ≥18 y, and with hemoglobin ≥100 g/L were randomly assigned 1:1 to receive daily iron (300 mg ferrous sulfate) or placebo + 0.40 mg folate from enrollment to birth. Iron status was assessed in maternal venous blood (at enrollment and at or near term) and cord blood. Primary outcomes were as follows: 1) maternal iron deficiency (ID) defined in 2 ways as serum ferritin (SF) <15 μg/L and body iron (BI) <0 mg/kg; 2) maternal ID anemia [ID + anemia (IDA); hemoglobin <110 g/L]; and 3) neonatal ID (cord blood ferritin <75 μg/L or zinc protoporphyrin/heme >118 μmol/mol). RESULTS: A total of 2371 women were randomly assigned, with outcomes for 1632 women or neonates (809 placebo/folate, 823 iron/folate; 1579 mother-newborn pairs, 37 mothers, 16 neonates). Most infants (97%) were born at term. At or near term, maternal hemoglobin was significantly higher (+5.56 g/L) for iron vs. placebo groups. Anemia risk was reduced (RR: 0.53; 95% CI: 0.43, 0.66), as were risks of ID (RR: 0.74; 95% CI: 0.69, 0.79 by SF; RR: 0.65; 95% CI: 0.59, 0.71 by BI) and IDA (RR: 0.49; 95% CI: 0.38, 0.62 by SF; RR: 0.51; 95% CI: 0.40, 0.65 by BI). Most women still had ID (66.8% by SF, 54.7% by BI). Adverse effects, all minor, were similar by group. There were no differences in cord blood iron measures; >45% of neonates in each group had ID. However, dose-response analyses showed higher cord SF with more maternal iron capsules reported being consumed (β per 10 capsules = 2.60, P < 0.05). CONCLUSIONS: Prenatal iron supplementation reduced anemia, ID, and IDA in pregnant women in rural China, but most women and >45% of neonates had ID, regardless of supplementation. This trial was registered at clinicaltrials.gov as NCT02221752.