Parmesan is considered safe during pregnancy regardless of pasteurization status. As a hard, aged cheese (typically aged 12–36 months), its low moisture content and long aging process create conditions where Listeria cannot survive — even if the original milk was unpasteurized.
Key Takeaway: Parmesan (Parmigiano-Reggiano) is a hard cheese and is considered safe during pregnancy whether pasteurized or unpasteurized. The same applies to other hard aged cheeses: aged cheddar, aged gouda, Pecorino Romano, Gruyère, and Manchego. Low moisture + long aging = inhospitable to Listeria.
Traditional Italian Parmigiano-Reggiano is made from raw (unpasteurized) milk and aged minimum 12 months. Despite being unpasteurized, it's considered safe because the aging process eliminates pathogenic bacteria. FDA guidelines do not restrict hard aged cheeses during pregnancy.
Parmesan provides excellent calcium (330mg per ounce — 33% of daily pregnancy needs) and protein (10g per ounce).
Bottom Line: Eat parmesan freely during pregnancy. Hard aged cheeses are considered safe regardless of pasteurization. One of the best calcium-dense cheese options available.