Intermountain Healthcare

Air Pollution and Pregnancy: Why It's Important to Reduce Exposure


Salt Lake City, UT -- (ReleaseWire) -- 07/20/2021 --Pregnancy is a wonderful time, but expectant mothers can also be concerned if air pollution might have an effect on their unborn baby.

Summer can be a bad time for air. Summer wildfires, fireworks and high temperatures all play a role in increasing the amount of summer air pollution. And of course, a big source of air pollution any time of year is automobile exhaust.

Studies have shown that air pollution can increase risk for miscarriage, stillbirth, preterm birth, and Sudden Infant Death Syndrome (SIDS). It may also lead to a slightly lower rate of fetal growth. High air pollution levels can have an effect even during the time when a woman conceives. "You may want to take that into consideration if you're planning to get pregnant," said Dr. Homewood.

With poor air quality across the west, Dr. Virginia Homewood, an OB/Gyn with Intermountain Healthcare in Salt Lake, offers some tips to help reduce exposure to air pollution for pregnant moms.

Five tips to avoid outdoor air pollution include:

1. Check local daily air quality at sites like
2. Don't exercise outside on high pollution days
3. Don't exercise outside at peak traffic times like rush hour
4. Don't let the car idle
5. Use the car recirculation setting to reduce the amount of exhaust fumes

"Indoor air pollution can also be a problem," said Dr. Homewood. She explains that many people don't realize air pollution can occur indoors. "Outdoor air pollution is a major contributor to indoor air pollution. But you can take steps to help reduce the amount of fine particulate pollution particles in your home."

Seven things to avoid indoor air pollution include:

1. Make sure to change your furnace filter regularly
2. Use a portable indoor HEPA air filter in the room most used
3. Use HEPA air filters with a MERV rating of 13-16
4. Do use an exhaust fan in the kitchen
5. Don't use a wood burning fireplace or burn candles or incense
6. Don't allow smoking inside the home or nearby
7. Don't spray volatile chemicals or cleaners inside the home

A High-Efficiency Particulate Arrestance (HEPA) filter with a MERV (Minimum Efficiency Reporting Value) rating of 13-16 is most effective at removing the smallest pollution particles. HEPA filters remove more than 99 percent of particulates. (These should not be confused with air purifiers that use UV light or electrostatic charges to kill viruses or bacteria).

HEPA filter MERV ratings range from 1 to 16. A low MERV rating (1 to 4) means the filter only traps large particles such as dust. A high MERV rating (13 to 16) means that particles less than 1 micron are removed, such as the PM2.5 particles in outdoor air pollution that cause poor health outcomes. However, HEPA filters do not remove radon or ozone, which can also be harmful to the lungs. For more information visit:

"An indoor air filter can help reduce the pollution particles in a room in your home," said Dr. Homewood. "Kitchens and rooms with wood burning fireplaces can also be a major source of dirty air. Place it one of those areas or where you spend most of your time. You could move it to your bedroom at night."

It takes a whole community to improve air quality. "We are all contributing to and affected by air pollution, whether we are young or old or have heart or lung disease or not," said Dr. Homewood. "The solutions to better air quality must be addressed by all of us as a community. If we don't take action, we will continue to see increased health costs and lower quality of life in our communities."

For more tips on having a healthy pregnancy, see Intermountain Moms.

About Intermountain Healthcare
Intermountain Healthcare is a nonprofit system of 25 hospitals, 225 clinics, a Medical Group with 2,600 employed physicians and advanced practice clinicians, a health insurance company called SelectHealth, and other health services in Utah, Idaho, and Nevada. Helping people live the healthiest lives possible, Intermountain is widely recognized as a leader in clinical quality improvement and in efficient healthcare delivery. For more information about Intermountain, visit, read our blogs, connect with us on Twitter and Facebook, or follow us on LinkedIn and YouTube.