Which statement has NOT been shown to reduce risk for preterm birth and fetal death?

• A. Antioxidant vitamins C and E
• B. Low-dose aspirin
• C. Supplemental calcium
• D. Folic acid

Answer: (A)

Not every prenatal supplement lowers the risk of preterm birth or fetal death; solid evidence supports some interventions but not others. Large randomized trials have consistently shown that antioxidant vitamins C and E do not reduce preterm birth or fetal death. In fact, these trials found no meaningful improvement in important pregnancy outcomes with C and E supplementation, and some analyses even raised concerns about potential harms at high doses.

By contrast, other measures have demonstrated benefits in certain populations. Low‑dose aspirin started in pregnancy for those at elevated risk lowers the chance of preeclampsia and related fetal complications. Supplemental calcium can reduce hypertensive disorders in women with low calcium intake. Folic acid is essential for neural tube defect prevention and is a standard component of prenatal care, with strong proven benefit for that purpose and potential positive effects on overall pregnancy outcomes in some studies.