The following is the suggested approximate composition of prenatal multivitamin/mineral supplements for use by women identified to be at high nutritional risk. (See the chart "Indications for Nutrient Supplementation" in Tab 1 for further information.)

If vitamin A is included, beta-carotene is preferred over retinol to reduce the risk of toxicity or other adverse reactions. Since calcium and magnesium may interfere with iron absorption, upper limits of 250 and 25 mg/dose, respectively, are recommended as a part of vitamin/ mineral supplements.

Some calcium supplements provide less than the recommended 600 mg of elemental calcium per tablet. It is advisable to take calcium supplements (e.g., calcium carbonate) with meals to promote absorption of the calcium.