DEET is the main ingredient in mosquito repellents. It has not been thoroughly studied in pregnancy, however it is a big issue now that Zika virus has been linked to such significant birth defects. Thai researches have found that daily use of DEET in pregnant women did not show harmful effects in pregnant. For countries where malaria and Zika are daily risks the recommendation is to use effects repellents containing DEET. Currently the benefits of avoiding a mosquito-borne infection outweigh the risks of DEET.