Are bug bombs safe to use while pregnant?

What does the evidence say about bug bombs and foggers during pregnancy?

1. Pregnant people are advised to avoid mixing and applying pesticides themselves. 1
2. Having a professional exterminator handle the job is unlikely to raise exposure high enough to increase pregnancy risk, which makes hiring it out a reasonable option over doing it yourself. 1
3. Pyrethrin and pyrethroid insecticides, the class most bug bombs and foggers are built on, enter the body mainly through ingestion, inhalation, and skin contact, and local irritation such as dermatitis or stomach upset typically shows up before any more serious systemic symptoms. 2
4. In one documented case, office workers who reentered a building two days after it was sprayed with a pyrethroid insecticide still developed shortness of breath, cough, headache, and nausea, and turning on the building's ventilation system afterward made symptoms worse because it stirred up insecticide that had settled into the ductwork. 3
5. Household exposure to pyrethroids most commonly happens through inhalation and ingestion from aerosols and sprays, and research has linked prenatal pyrethroid exposure with impaired birth outcomes and measures of child development. 4

Is bug bombs and foggers safe in each trimester?

• First trimester. Organ development is happening rapidly in the first trimester, so this is a reasonable time to be extra cautious about airborne chemical exposure and let someone else handle both the fogging and the return-and-air-out step.
• Second trimester. The same avoidance approach still applies. If pest control is genuinely needed, hiring a professional exterminator for the job is a reasonable middle ground, since MotherToBaby's guidance is that this route is unlikely to raise your exposure enough to increase pregnancy risk.
• Third trimester. Late pregnancy is not the time to be the one holding the fogger canister or doing the cleanup afterward. Have someone else manage it, and don't rush back into a space that was just fogged.