UPPAbaby Car Seat Lawsuit: Breathing and Choking Hazard Alleged in Infant Seats

Case Overview: A class action alleges UPPAbaby infant car seats (Mesa Max, Mesa V2, and Aria) have a design flaw causing babies to slump into unsafe "C"-shaped postures, potentially leading to respiratory problems and choking.

Consumers Affected: California parents who purchased an UPPAbaby Mesa Max, Mesa V2, or Aria car seat.

Court: U.S. District Court for the Central District of California

UPPAbaby is facing a proposed class action lawsuit from California parents who say the company knowingly sold defective infant car seats that can cause babies to slump into unsafe positions, leading to discomfort, respiratory problems, and even choking.

According to the complaint, UPPAbaby’s Mesa Max, Mesa V2, and Aria car seats have a design flaw that causes infants to slide into a “C”-shaped posture, pressing their chins to their chests—a position that can block airways and make breathing difficult. 

Plaintiffs claim the company concealed the issue despite receiving numerous consumer complaints and continued marketing the seats as safe and ergonomically designed.

Parents Describe Babies Slumping into Unsafe "C"-Shape Posture

California parents Pamela Mossazadeh, Kellie Cusick, Alexander Pena, and Joey Zaokopny filed the lawsuit after their experiences with UPPAbaby’s Mesa Max model. Each said they purchased the seat after researching its safety features and reputation, with many citing previous positive experiences with the brand.

But problems surfaced quickly after use. Mossazadeh, a nurse, said her baby showed signs of distress and difficulty breathing shortly after birth when placed in the seat, even hospital staff questioned the baby's posture. For Cusick, the issue became alarming when her infant began foaming at the mouth and crying uncontrollably in the car. 

Pena and Zaokopny both observed similar slumping postures and respiratory discomfort after removing the infant insert as directed. In all cases, the parents eventually abandoned the car seats, switching to different brands after UPPAbaby failed to offer refunds or meaningful solutions.

Lawsuit Alleges UPPAbaby Concealed Defect Despite Complaints

At the center of the complaint is the claim that UPPAbaby’s car seat design leads to a hazardous chin-to-chest posture that can obstruct a baby’s airway. The issue reportedly worsens once the removable infant insert—designed to be used until the baby exceeds 11 pounds—is taken out.

Despite marketing language that touts the seats’ ability to “optimize body positioning,” plaintiffs allege the company has known about the defect for years and has actively concealed it from customers. 

They point to complaints filed with the National Highway Traffic Safety Administration (NHTSA), including one in which an infant’s oxygen levels dropped so dangerously that medical intervention was required. Similar warnings and reviews are scattered across retailer websites like Amazon, Babylist, and UPPAbaby’s own site.

Baby Product Safety Continues to Spark Legal Action

The lawsuit against UPPAbaby is part of a broader trend of legal action surrounding the infant product industry. Dorel Juvenile Group, maker of the Safety 1st brand, is also facing a lawsuit over a recalled car seat whose headrest was found to pose a choking hazard. 

Nuna is under fire for allegedly selling defective Rava convertible car seats, while Fisher-Price and Mattel have been sued over potentially suffocating swings and shock-prone sound machines.

In this latest lawsuit, the parents want to represent anyone in California who purchased an UPPAbaby Mesa Max, Mesa V2, or Aria car seat, in their claims of violations of California’s Consumer Legal Remedies Act, Unfair Competition Law, Magnuson-Moss Warranty Act, Song-Beverly Consumer Warranty Act, and more. 

They are seeking damages, injunctive relief, fees, costs, and interest.

Case Details

• Lawsuit: Mossazadeh et al v. Monahan Products, LLC
• Case Number: 2:25-cv-04862
• Court: U.S. District Court for the Central District of California

Plaintiffs' Attorneys

• Cody R. Padgett, Shahin Rezvani, and Nathan N. Kiyam (Capstone Law APC)

Do you own an UPPAbaby Mesa Max, Mesa V2, or Aria car seat? Have you noticed any issues with your baby's posture or breathing? Share your experience below.