In every pregnancy, a woman starts out with a 3-5% chance of having a baby with a birth defect. This is called her background risk. This sheet talks about whether exposure to mold may increase the risk for birth defects above that background risk. This information should not take the place of medical care and advice from your health care provider.

What is mold?

Molds are fungi that can be found both indoors and outdoors. They grow best in warm, damp, and humid places. Molds spread by making spores that are able to live almost anywhere.

Mold can be many different colors and usually grows in damp or water damaged areas. Mold can also have a musty, earthy smell. Four common household molds are Cladosporium, Penicillium, Alternaria, and Aspergillus.

Can mold make me sick?

Molds themselves won’t make you sick, but some molds can produce substances, called toxins, that can cause health problems. Mold exposure can cause symptoms in some people such as allergic reactions including stuffy nose, eye irritation, rashes, and wheezing, and possibly fever or shortness of breath. Not everyone will have these symptoms. People who have a weak immune system or have a chronic (ongoing) respiratory condition (e.g. asthma) may be more sensitive to mold. If mold exposure is causing you to have any of these symptoms, talk to your health care provider.

How do I keep mold out of buildings and homes?

  • Keep the moisture levels in the house as low as possible, but on average lower than 50%.
  • Use an air conditioner or dehumidifier during humid months.
  • Use exhaust fans in kitchens and bathrooms.
  • Clean bathrooms with mold killing products. Wear non-porous gloves and eye protection; and have good air ventilation while cleaning.
  • Do not install or put carpet in bathrooms and basements.

How can I clean up mold after a water leak or a flood?

  • Wear a special mask that can keep the mold spores out of the air you breathe, such as an N95 respirator. N95 respirators block 95% of small particles (like mold spores) from getting into the air you breathe. For it to work properly, make sure to follow all instructions on the N95 respirator packaging.
  • Wear non-porous gloves, which are made from natural rubber, neoprene, nitrile, polyurethane, or PVC.
  • Wear eye protection, such as goggles without air vents in them.
  • Have good air ventilation while cleaning by keeping doors and windows open, air vents and fans turned on.
  • Remove all items that have been wet for more than 48 hours if they cannot be thoroughly cleaned and dried. This includes carpeting, upholstery, wallpaper, drywall, floor and ceiling tiles, insulation material, clothing, leather, paper, wood, and food.
  • Remove mold growth from hard surfaces by using commercial mold cleaning products or a bleach solution (1 cup bleach in 1 gallon of water). Do not mix bleach with ammonia or other household cleaners. Always follow use and storage directions on the labels.
  • If you are sensitive to mold or cleaning products, consider asking someone else to clean for you, particularly in areas with poor ventilation.
  • Professional companies can also be hired to clean up the flooded basement or other household areas.

I have heard that Stachybotrys is a mold that is worse than the common household molds. Should I be worried if I have this mold in my home?

Stachybotrys is a greenish-black mold. While it is not very common in homes, it is not rare either. There are a few reports of molds such as Stachybotrys causing bleeding in the lungs in infants. These case reports are rare, and there is not enough information to prove a connection.

If you think that your home may have Stachybotrys, you do not need to have it tested. Since all molds could cause health problems, they should all be removed as soon as possible. Stachybotrys should be removed in the same way as any other type of mold.

I am pregnant and there is mold in my home. Is my pregnancy at risk?

There are no human studies looking at exposure to mold during pregnancy. Studies in animals have shown that mold toxins can increase the risk of birth defects when eaten. Currently, however, there is no proven risk to a pregnancy from exposure to airborne mold.

If you are pregnant and you have found mold in your home, you should have it removed as soon as possible. Talk to your health care provider if you are experiencing any illness that you think could be from mold exposure.

What if there is mold in my home while I’m breastfeeding?

Since mold in the home may make both the mother and baby sick, it should be removed as soon as possible. There are no studies looking at infant health when exposure to mold happens during breastfeeding. Be sure to talk to your health care provider if you have questions about breastfeeding.

What if the father of the baby is exposed to mold?

In general, exposures that fathers have are unlikely to increase risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures and Pregnancy at http://mothertobaby.wpengine.com/fact-sheets/paternal-exposures-pregnancy/pdf/.