Carbon monoxide is an odorless and colorless gas that can cause serious health problems. [1,2] Not only is carbon monoxide harmful to your health, but it can also endanger your developing baby. If you are exposed to a large amount of carbon monoxide, poisoning can occur. Even low levels of exposure to carbon monoxide can lead to poisoning over time because the gas continues to build up in your blood. What many expecting moms may not be aware of is that you can be exposed to carbon monoxide in your home without ever knowing. Once you develop symptoms of carbon monoxide poisoning, injury to you or your baby may have already occurred. In severe cases, carbon monoxide poisoning can lead to death. It is important for expecting moms to take precautions to prevent carbon monoxide exposure.
How does carbon monoxide cause injury?
Hemoglobin is a substance in your blood that carries oxygen to the cells in your body. After exposure to carbon monoxide, your lungs absorb the dangerous gas and it binds to hemoglobin.  Once carbon monoxide has bound to hemoglobin, it prevents oxygen from binding. This prevents your cells from getting the oxygen that they need to function and survive. Eventually, continued lack of oxygen will result in injury to the cells and tissues in your body. Carbon monoxide also directly damages your body’s cells, causing further injury.
Developing babies are particularly vulnerable to the effects of carbon monoxide. If you are exposed to carbon monoxide during pregnancy, it will attach to your hemoglobin and travel through your blood to your baby’s blood by crossing the placenta. [4,5] Carbon monoxide binds even more effectively to your baby’s hemoglobin than to your hemoglobin. This means that your baby will have a higher level of carbon monoxide in his or her blood. It is also more difficult for babies to eliminate carbon monoxide, so it stays in their blood longer. Carbon monoxide will prevent oxygen from getting to the baby’s cells and can result in serious injury or death. Since the baby’s developing organs are more vulnerable to injury, harm can occur even in cases where poisoning was not severe in the mom. During the early stages of pregnancy, carbon monoxide exposure can lead to birth defects. Exposure during later stages of pregnancy can lead to brain damage or death of the baby.
How can I be exposed to carbon monoxide?
There are many ways that carbon monoxide exposure can occur. Carbon monoxide is produced by the burning of fuels, such as coal, wood, natural gas, petroleum, methane, or propane.  It is found in the fumes that are emitted when operating stoves, lanterns, gas ranges, or generators. It is also produced by burning wood or coal in a fireplace or grill. Vehicle exhaust and cigarette smoke are other sources of carbon monoxide.
Improper use of generators is a frequent cause of carbon monoxide poisoning. Generators should never be used inside the house, garage, basement, or on a porch or deck.  They should only be used outside and should be placed 20 feet away from your home. Running vehicles or machinery inside of a garage can also lead to carbon monoxide exposure.  Vehicles should never be left running inside of a garage or enclosed structure, even if the garage door is open. It is also important to never start or operate snow blowers, lawn mowers, chain saws, or pressure washers inside of an enclosed area. Carbon monoxide exposure can also occur from improper use of heating or cooking appliances. Never use gas or briquette grills indoors or in an enclosed area. Portable gas heaters should also never be used indoors, and non-electric cooking ranges should not be used for heat.
You can also be exposed to carbon monoxide from malfunctioning appliances in your home. Boilers, furnaces, and hot-water heaters can emit carbon monoxide if they are not properly maintained. They should be serviced by a qualified technician annually to ensure that they are functioning properly.  Gas appliances must be properly vented when they are installed. If you have a chimney, it is important to have it checked and cleaned every year. Expecting moms should also avoid smoking and avoid exposure to second-hand smoke.
Carbon monoxide alarms
The best way to protect yourself and your baby from carbon monoxide exposure is to install a battery-operated carbon monoxide detector in your home. Detectors should be installed in a place where it will wake you up, such as outside your bedroom, in case of emergency. Batteries should be checked or replaced every 6 months, and the carbon monoxide detector should be replaced after 5 years. Detectors can warn you when levels of carbon monoxide are within a range that could endanger you and your baby. They enable you to remove yourself from the source of carbon monoxide exposure before injury.
Symptoms of carbon monoxide poisoning include: dizziness, headache, vomiting, nausea, weakness, chest pain, and confusion. If you develop any symptoms of carbon monoxide poisoning or you think that you may have been exposed to carbon monoxide, you should call 911. Carbon monoxide poisoning is a life-threatening emergency. The faster you can seek treatment, the less likely that you or your baby will have permanent injury.
- Centers for Disease Control and Prevention. Carbon Monoxide Poisoning .
- United States Environmental Protection Agency. Carbon Monoxide’s Impact on Indoor Air Quality.
- Chiew AL, Buckley NA. Carbon monoxide poisoning in the 21st century.
- J Greingor, J Tosi, S Ruhlmann, and M Aussedat. Acute carbon monoxide intoxication during pregnancy. One case report and review of the literature.
- Delomenie M, Schneider F, Beaudet J, et al. Carbon Monoxide Poisoning during Pregnancy: Presentation of a Rare Severe Case with Fetal Bladder Complications.
- Gozubuyuk AA, Dag H, Kacar A, Karakurt Y, et al. Epidemiology, pathophysiology, clinical evaluation, and treatment of carbon monoxide poisoning in child, infant, and fetus.
- Centers for Disease Control and Prevention. Carbon Monoxide Poisoning: Carbon Monoxide – Generator Safety Fact Sheet.
- New York State Department of Health. Fact Sheet: What You Need to Know about Carbon Monoxide.
- Centers for Disease Control and Prevention. Carbon Monoxide Poisoning: Frequently Asked Questions.