Ay, mamsh, this is a safety question na talaga dapat i-check with your OB, better safe than sorry, diba? Mosquito sprays during pregnancy can be tricky, so please ask your doctor specifically about Baygon Mat or any insecticide you're thinking of using, they'll know what's safest for you and baby.
In the meantime, a few of us moms just go with mesh screens, mosquito nets, or electric fans (mosquitoes hate strong air) to protect ourselves. Mas peace of mind, walang worry! Let me know what your doc says, okay? Take care!