Blue cheese — sometimes spelled “bleu cheese” — is known for its blueish hue and potent smell and flavor. You’ll regularly find this popular dairy product in salad dressings and sauces, or served alongside fruit and nuts or other cheeses.

Some of the most common varieties are Stilton, Roquefort, and Gorgonzola (1).

Still, because it’s a mold-ripened cheese often made with unpasteurized milk, you may wonder whether it’s safe to eat during pregnancy.

This article explains whether pregnant women can eat blue cheese.

The risks of eating blue cheese during pregnancy have nothing to do with the fact that this dairy product is manufactured using mold, as these specific molds are safe to consume.

Instead, because most blue cheese is made with unpasteurized milk, it carries a higher risk of contamination with Listeria monocytogenes.

This bacterium can cause listeriosis, a foodborne illness that presents much like the flu or stomach bug (2).

Some of the most common listeriosis symptoms in pregnant women are fever, aches and pains, digestive upset, and headaches. More severe symptoms include stiff neck, confusion, convulsions, and loss of balance (3).

These may be a sign that Listeria has entered into the mother’s nervous system, where it can cause bacterial meningitis, or inflammation around the brain and spinal cord (4, 5).

Listeriosis symptoms are often mild for pregnant women, and many may not even realize they have it. However, Listeria can cross the placenta and may be fatal to your unborn baby (3).

While listeriosis is fairly rare, pregnant women are up to 20 times likelier to get it than the general population (6).

Pasteurization, which uses mild heat to partially sterilized certain foods, kills Listeria. However, relatively few blue cheeses are pasteurized, leaving it at a higher risk of bacterial contamination.

Is all blue cheese at risk?

Keep in mind that cooking can kill Listeria. As such, thoroughly cooked dishes, such as pizza with blue cheese, are likely safe to eat while pregnant.

One study using raw milk showed that temperatures of 131°F (55°C) significantly reduced the activity of Listeria (7).

Though less common, some blue cheeses are made with pasteurized milk. You can tell by looking at the product label.

If you’re pregnant, you should avoid any blue cheese that includes raw milk. Unpasteurized dairy products are required by law to have a disclosure in most U.S. states.

What about blue cheese dressing?

Blue cheese dressings often combine blue cheese with mayonnaise, buttermilk, sour cream, vinegar, milk, and onion and garlic powder, though other variations exist.

The milk and blue cheese in this dressing may be at risk of Listeria contamination. Blue cheese dressing may or may not be made using pasteurized ingredients.

To be on the safe side, pregnant women may wish to avoid blue cheese dressing. If you decide to buy it, select a product that has been pasteurized.

SUMMARY

As it’s often made with unpasteurized milk, blue cheese increases your risk of Listeria poisoning, which is extremely dangerous for unborn babies. If you’re pregnant, it’s best to avoid blue cheese products or only buy ones that use pasteurized milk.

Symptoms of Listeria poisoning typically appear within a few days of eating the contaminated food. However, some people may not experience symptoms for up to 30 days.

If you’re pregnant and have eaten blue cheese, don’t panic. Monitor your health and look for symptoms like vomiting, diarrhea, or a fever above 100.5°F (38°C) (9).

Call your healthcare provider if you start to feel sick or think you may have listeriosis symptoms.

A blood test can be performed to confirm the infection, and — if diagnosed early — sometimes antibiotics can be used for treatment (3).

SUMMARY

If you’ve eaten blue cheese while pregnant, don’t panic. Monitor any symptoms and contact a health professional if you suspect you have listeriosis.

Blue cheese is a soft, mold-ripened cheese that many people enjoy on salads and in sauces.

It’s often made with unpasteurized milk, which puts it at high risk of causing listeriosis, a potentially dangerous infection for pregnant women.

Thus, pregnant women should avoid most blue cheese, as well as products that contain it.

Still, a few blue cheeses are made with pasteurized milk, and these are safe to consume.

If you have eaten unpasteurized blue cheese while pregnant, the best course of action is to monitor your symptoms and call your healthcare provider if you’re concerned.