A very large 2025 online/2026-print cohort found no overall major-malformation increase with first-trimester Z-drug exposure, but 92.1% of exposures were zolpidem.
- Public-source certainty descriptor
- moderate for zolpidem overall malformations; low for other Z-drugs and specific defects; not GRADE
- Formal appraisal
- Not started — full text and independent appraisal pending
- Exposure window
- first trimester
- Comparator
- Z-drug exposed versus unexposed
4,281,579 pregnancies; 11,652 Medicaid and 10,862 MarketScan exposed; pooled adjusted RR 1.01 (95% CI 0.95-1.08); 92.1% zolpidem.
Dispensing exposure, live births, residual confounding, and inadequate power/generalizability for zaleplon, eszopiclone, and zopiclone.
Sources, citation controls, and verification state
Linked sources
- adjusted cohortEXT-029 · Not formally appraised
- PMID
- 41432941
- DOI
- Pending DOI verification
- Exact locator
- Pending exact table/figure/page/supplement locator
- Access date
- 2026-07-29
- Integrity check
- Same-day source surveillance recorded; source-by-source correction/retraction verification remains pending
- Internal verification
- Source-linked; independent external verification pending