Legacy Pregnancy Category Lookup
Bounded off line reference: FDA legacy pregnancy category framework, not a live medication-specific category database. Explicit topics legacy, authority. No full/live authority, clinical diagnosis, safe-use approval or universal individual outcome.
Description
Historical FDA pregnancy letters condensed information that current prescription labeling presents in narrative sections.
Historical FDA pregnancy letters condensed information that current prescription labeling presents in narrative sections.1
This tool returns a short stored explanation of the legacy categories and their limitations; it does not assign a category to a drug.
When to use Legacy Pregnancy Category Lookup
Read a bounded educational reference for one of the supported topics.
How to use Legacy Pregnancy Category Lookup and how it works
- Choose a supported exact topic from the table below.
- Enter that topic token and run the tool.
- Read result.text and its scope or precision limitations.
- Correct an unsupported token before rerunning; use an independently applicable reference when more detail or current evidence is required.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| topic | Topic. Use the units and matching context stated in the calculation below. | string | Required; other constraints below |
Choose one exact case-sensitive topic: legacy, authority. The implementation matches that token to a stored text record and returns result.text unchanged. Unknown tokens, blank strings and wrong input types are errors; no case folding or live lookup occurs. These are bounded educational records, not a calculation from observations, a proof search, a patient assessment or an arbitrary-precision value. The supported topic inventory below identifies the available records.
text=storedInventory[exactTopic] Apply the input ordering, units and branch conditions stated above.
| Exact topic token | Record selected |
|---|---|
| legacy | Stored legacy reference. |
| authority | Stored authority reference. |
| Output field | Meaning | Value type |
|---|---|---|
| result | Object containing the calculated or selected fields below. | object |
| result.text | Exact stored educational record selected by the supported topic token. | string |
{
"input": {
"topic": "legacy"
},
"output": {
"result": {
"text": "US FDAlegacyA/B/C/D/Xpregnancyletters were replaced for prescription drugs/biologics by narrative PregnancyandLactationLabelingRulesections. Do not treat a letter as quantitative fetal risk or current prescribingapproval."
}
}
}Limitations and assumptions
Patient context, drug formulation, route, sampling time, assay units and applicable clinician-verified protocol must be independently established. The output supplies no dosing, titration, switching or administration instruction.
This is a stored text inventory. It does not calculate from measurements, obtain live data, prove an infinite assertion, classify a patient or certify arbitrary precision.
All fields require explicit values. Unexpected fields, wrong types, nonfinite numbers and sparse arrays are rejected. Alignment, bounds and supported-token rules are explained above; extremely large inputs or nonfinite results can also fail. Input errors differ from successful false comparisons, unavailable-domain flags and empty match lists.
FDA explains that pregnancy letter categories were removed from prescription labeling in favor of more informative narrative risk information. This stored legacy reference does not assign a drug category.2
Alternative or Complementary methods
Use Lactation Risk Lookup for a complementary operation: Lactation-related drug review depends on the product, exposure, infant context and source edition.
Use Beers Criteria Flagger for a complementary operation: Beers criteria are medication-review criteria tied to an edition and relevant patient circumstances.
References
Similar or alternative tools
- Lactation Risk Lookup
Lactation-related drug review depends on the product, exposure, infant context and source edition.
- Beers Criteria Flagger
Beers criteria are medication-review criteria tied to an edition and relevant patient circumstances.