A bilateral condition is a medical condition that can affect both sides of the body symmetrically — both hips, both knees, both eyes, both kidneys. Common bilateral conditions in cats include hip dysplasia, cataracts, polycystic kidney disease (PKD), and hypertrophic cardiomyopathy (HCM, which affects both sides of the heart wall).
Why it matters for insurance
The insurance risk: if your cat is diagnosed with a bilateral condition on one side before your policy starts, some insurers will classify the other side as a pre-existing condition — even though the second side hasn’t been diagnosed yet.
Example: Your Maine Coon develops early-stage HCM in the left ventricle wall, noted by a vet before you enroll with a new carrier. When HCM progresses to the right ventricle (common with this condition), the carrier argues it’s pre-existing because bilateral HCM is a single systemic condition.
This is not universal — carriers handle bilateral conditions differently — but it’s a documented pattern across multiple carriers including Healthy Paws (referenced in published Trustpilot reviews).
How different carriers handle bilateral conditions
- Most carriers: A bilateral condition diagnosed on one side before enrollment may be excluded on both sides
- Some carriers (varies by policy): Only the diagnosed side is excluded; the other side is covered until symptoms appear
- Trupanion: Published policy language addresses bilateral conditions explicitly — check current policy terms before enrolling
Practical implications
For owners of breeds with known bilateral hereditary risks — Maine Coon (HCM), Persian (PKD, brachycephalic issues), Bengal (PK-Def) — the bilateral condition clause is one of the most important policy terms to read before enrolling.
Enroll as early as possible. A kitten with no prior vet notes is the cleanest starting point. Once any bilateral condition appears in the medical record, the insurance math changes materially.
Disclaimer: Policy terms vary significantly between carriers. Always read the full policy document for specific bilateral condition language before purchasing. This content is for comparison purposes only.