{
  "dataset": "prenatal-vitamin-d-label-census",
  "title": "Prenatal vitamin D label census — IU per daily directed dose vs the 600 IU pregnancy RDA, 1,000 / 2,000 IU and the 4,000 IU trial dose",
  "sourcePage": "https://verifiedsupplementdata.com/vitamin-d/for-women/",
  "license": "CC BY 4.0",
  "licenseUrl": "https://creativecommons.org/licenses/by/4.0/",
  "attribution": "Verified Supplement Data (2026), Prenatal Vitamin D Label Census",
  "dateModified": "2026-09-14",
  "methodology": "Every on-market label in the NIH Dietary Supplement Label Database matching \"prenatal\" was read in full; labels with \"prenatal\" in the product name were kept. Vitamin D per day = the Supplement Facts vitamin D row for the labelled serving × the label's maximum daily servings; mcg converted at 40 IU/mcg. Percentages are stated against labels that declared vitamin D. Every exported figure was recomputed in both halves of the read order and agreed within 8 points (shares) or 25% (medians). The corpus includes prescription-only prenatals as well as retail products; they are not separated.",
  "referenceDoses": {
    "pregnancyRdaIU": 600,
    "upperLimitIU": 4000,
    "trialDoseIU": 4000,
    "trialPmid": "21706518"
  },
  "source": "NIH Dietary Supplement Label Database (DSLD) v9",
  "sourceUrl": "https://dsld.od.nih.gov/",
  "onMarket": 808,
  "labelsRead": 808,
  "prenatalsAnalysed": 444,
  "withVitaminD": 391,
  "findings": {
    "declaresVitaminDPct": 88.1,
    "below1000IUPct": 72.1,
    "atLeast1000IUPct": 27.9,
    "atLeast2000IUPct": 7.7,
    "atLeast4000IUPct": 2.6,
    "p25IU": 400,
    "p75IU": 1000,
    "d3OfStatedFormPct": 96.6,
    "d2OfStatedFormPct": 3.4,
    "folateOnPanelPct": 86.7,
    "ironOnPanelPct": 74.5,
    "gummyMedianIU": 800
  },
  "validation": {
    "method": "split-half by DSLD read order",
    "checked": [
      "most prenatals declare vitamin D",
      "median vitamin D per day (IU)",
      "share below the 600 IU pregnancy RDA",
      "share at or above 1,000 IU",
      "share reaching the 4,000 IU trial dose",
      "share below 1,000 IU",
      "share at or above 2,000 IU",
      "bottom-quarter dose (p25, IU)",
      "top-quarter dose (p75, IU)",
      "D3 is the declared form",
      "gummy median (IU)",
      "folate on the panel",
      "iron on the panel"
    ],
    "held_in_both_halves": [
      "most prenatals declare vitamin D",
      "share at or above 1,000 IU",
      "share reaching the 4,000 IU trial dose",
      "share below 1,000 IU",
      "share at or above 2,000 IU",
      "bottom-quarter dose (p25, IU)",
      "top-quarter dose (p75, IU)",
      "D3 is the declared form",
      "gummy median (IU)",
      "folate on the panel",
      "iron on the panel"
    ],
    "failed": [
      "median vitamin D per day (IU)",
      "share below the 600 IU pregnancy RDA"
    ],
    "n": 444,
    "detail": {
      "most prenatals declare vitamin D": {
        "half_a": 90.1,
        "half_b": 86,
        "holds": true
      },
      "median vitamin D per day (IU)": {
        "half_a": 400,
        "half_b": 600,
        "holds": false
      },
      "share below the 600 IU pregnancy RDA": {
        "half_a": 56,
        "half_b": 44.5,
        "holds": false
      },
      "share at or above 1,000 IU": {
        "half_a": 25.5,
        "half_b": 30.4,
        "holds": true
      },
      "share reaching the 4,000 IU trial dose": {
        "half_a": 2,
        "half_b": 3.1,
        "holds": true
      },
      "share below 1,000 IU": {
        "half_a": 74.5,
        "half_b": 69.6,
        "holds": true
      },
      "share at or above 2,000 IU": {
        "half_a": 8,
        "half_b": 7.3,
        "holds": true
      },
      "bottom-quarter dose (p25, IU)": {
        "half_a": 400,
        "half_b": 400,
        "holds": true
      },
      "top-quarter dose (p75, IU)": {
        "half_a": 1000,
        "half_b": 1000,
        "holds": true
      },
      "D3 is the declared form": {
        "half_a": 97.2,
        "half_b": 96.1,
        "holds": true
      },
      "gummy median (IU)": {
        "half_a": 600,
        "half_b": 800,
        "holds": true
      },
      "folate on the panel": {
        "half_a": 87.4,
        "half_b": 86,
        "holds": true
      },
      "iron on the panel": {
        "half_a": 78.4,
        "half_b": 70.7,
        "holds": true
      }
    }
  }
}