713 F. App'x 11
2d Cir.2017Background
- Mirena is an LNG-releasing IUD; plaintiffs allege it perforated, embedded in, or migrated from their uteri (secondary perforation) after insertion.
- Plaintiffs sued Bayer in a consolidated MDL (~1,300 cases) asserting product-liability and related state-law claims; several cases underwent full discovery.
- Central dispute: whether Mirena can cause secondary (post-insertion) uterine perforation — Bayer warned about perforation during insertion but not about secondary perforation.
- Plaintiffs offered three categories of evidence for general causation: select Bayer employee statements, a 2014 Mirena label change, and expert testimony asserting mechanisms for secondary perforation.
- The district court excluded plaintiffs’ general-causation experts under Daubert (experts assumed the disputed phenomenon and relied on untested, litigation-driven theories) and then granted Bayer summary judgment because plaintiffs lacked admissible evidence establishing general causation.
Issues
| Issue | Plaintiff's Argument | Defendant's Argument | Held |
|---|---|---|---|
| Admissibility of plaintiffs’ general-causation experts under Rule 702/Daubert | Experts offered plausible mechanisms for secondary perforation; their methodology is reliable enough for jury consideration | Experts’ opinions are unreliable, litigation-driven, not peer-reviewed, not generally accepted, and premised on the disputed fact | Trial court did not abuse discretion — experts excluded under Daubert |
| Whether expert testimony is required to prove general causation for state-law claims | Party admissions and label change can substitute for expert proof in some jurisdictions | State law typically requires expert proof for causation in complex medical-device cases; plaintiffs lack sufficient admissible evidence | Summary judgment affirmed: plaintiffs cannot prove general causation without experts |
| Sufficiency of Bayer employee emails and internal materials as admissions proving general causation | Short email excerpts and a PowerPoint slide show Bayer acknowledged secondary perforation | Emails report adverse-event anecdotes (not admissions); slide is ambiguous and lacks causal explanation | Not enough: documents are anecdotal/ambiguous and cannot replace expert evidence |
| 2014 Mirena label change as evidence of causation | Label language acknowledging perforation may indicate Bayer accepted secondary perforation risk | Label language is cryptic and, at most, suggests hypothetical possibility; does not establish causation more likely than not | Label change insufficient to establish general causation |
Key Cases Cited
- Daubert v. Merrell Dow Pharm., 509 U.S. 579 (general principles for admissibility of expert testimony)
- Kumho Tire Co. v. Carmichael, 526 U.S. 137 (Daubert gatekeeping applies to all expert testimony and methodology review)
- Zuchowicz v. United States, 140 F.3d 381 (abuse-of-discretion standard for exclusion of expert testimony)
- Amorgianos v. Nat’l R.R. Passenger Corp., 303 F.3d 256 (Daubert factors non-exhaustive and context-specific)
- Barnes v. Anderson, 202 F.3d 150 (expert medical opinion usually required to show causation)