Lighting mosquito coils may have an effect on pregnant women, need to pay attention to avoid the appearance, so as not to cause adverse consequences. Mosquito coil is the use of high temperature combustion effect, the insecticide slowly released into the air, mosquito repellent effect is greater than the effect of killing mosquitoes. It contains toxic ingredients such as organophosphates, carbamates, pyrethroids, etc., of which organophosphates are the most toxic, pyrethroid toxicity is the weakest, slightly toxic. Regular manufacturers of mosquito coils whose toxic ingredients are lower than the national standard, usually no harm to the human body. Although the regular manufacturers of mosquito coils on the human body without obvious harm, but the closed space ignited mosquito coils, concentration is higher, pregnant women with a sensitive sense of smell, more sensitive to the smell, and the respiratory tract is susceptible to prolonged exposure to this environment may be uncomfortable symptoms, may suffer from respiratory disease probability increases. During pregnancy can take physical measures to prevent mosquitoes, such as the use of screens, mosquito nets and other anti-mosquito measures.