Store-bought mayonnaise is considered safe during pregnancy — commercial mayo is made with pasteurized eggs and vinegar (which inhibits bacterial growth). Homemade mayonnaise using raw eggs should be avoided due to Salmonella risk.
Key Takeaway: Commercial mayo (Hellmann's, Duke's, store brands) = considered safe. Made from pasteurized eggs. Homemade mayo with raw eggs = avoid. Restaurant mayo = usually commercial and safe, but ask if you're at a restaurant that makes their own.
Store-bought mayo is actually one of the safest condiments available — the combination of pasteurized eggs, vinegar (acidic pH inhibits bacteria), and salt creates a hostile environment for pathogen growth.
Bottom Line: Store-bought mayo = safe. Homemade with raw eggs = avoid. Don't confuse mayo safety with the safety of what it's mixed into — chicken salad, tuna salad, and egg salad have separate concerns (temperature, storage time).