Is pest control spray safe during pregnancy?

What does the evidence say about professional pest control spray during pregnancy?

1. Having a home or workplace sprayed by a professional exterminator is unlikely to create pesticide exposure high enough to raise the risk to a pregnancy. 1
2. Most animal studies of common pesticides, and human studies of pesticide spraying such as malathion, have not found a consistent increase in birth defects above the usual background rate. 1
3. In one New York City cohort, every pregnant participant reported some insecticide exposure during pregnancy, whether from an exterminator's spray, a spray can, or a pest bomb, and switching households to integrated pest management (sealing entry points, boric acid and low-toxicity bait placed directly into cracks, and glue traps) measurably lowered the insecticide levels detected in mothers' blood at delivery compared with routine spraying. 2
4. Pyrethroids, the insecticide class most commonly used in professional pest control today after older organophosphates were withdrawn from residential registration in 2000 and 2001, are far more toxic to insects than to mammals, but a research review cautions they aren't harmless to people and that their breakdown products have turned up in breast milk. 3
5. Once a pesticide is applied indoors, its residue can sit on surfaces for months rather than breaking down quickly, since indoor spaces lack the sunlight and moisture that speed up degradation outdoors, which is one reason wiping down surfaces you'll touch matters more than just waiting a few hours before going back in. 4

Is professional pest control spray safe in each trimester?

• First trimester. The first trimester is when many people are most cautious about any chemical exposure, since this is when major organs are forming. The available data on professional exterminator visits doesn't point to a higher-risk window, but choosing to be out of the house during and shortly after spraying is a reasonable extra precaution now.
• Second trimester. The same general guidance carries through the second trimester: routine professional pest control is considered low-risk, and integrated pest management, sealing entry points, bait stations, and boric acid placed directly into cracks, can cut down how often spraying is needed at all.
• Third trimester. Late pregnancy doesn't change the guidance, but if a service is scheduled close to your due date, consider timing it so you have a day to ventilate and wipe down surfaces you'll touch, before you're managing a newborn and less able to keep sprayed areas off-limits.