Pregnancy Nutrition Calculator
See exactly how your nutrient needs change by trimester — and compare them to the non-pregnant baseline. Based on NIH Dietary Reference Intakes and WHO guidelines.
This tool provides general reference values only. Individual needs vary. Always follow your healthcare provider's specific recommendations for your pregnancy.
| Nutrient | Non-pregnant | Your need | Change |
|---|
Recommended weight gain (IOM guidelines)
Key foods for your most critical nutrients
Values are Recommended Dietary Allowances (RDAs) from the NIH Dietary Reference Intakes unless noted as Adequate Intake (AI). Individual needs vary — always follow your healthcare provider's guidance.
Why do nutrient needs change during pregnancy?
Pregnancy dramatically increases demand for several nutrients. Folate is needed for neural tube formation — critical in the first 28 days, often before a pregnancy is confirmed. Iron needs nearly double to support increased blood volume and fetal development. Calcium supports fetal bone development; if intake is insufficient, the body draws calcium from the mother's bones. Iodine is essential for fetal brain development, especially in the first trimester when the fetus depends entirely on the mother's supply.
Calorie needs increase modestly — roughly 340 kcal/day additional in the 2nd trimester and 450 kcal/day in the 3rd trimester — while protein needs increase throughout. The focus should be on nutritional quality, not simply eating more.
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