Brazilian Keratin Treatment (BKT) is generally considered safe to do during pregnancy, as long as certain precautions are taken. BKT involves the use of chemicals in order to produce a straightening effect on the hair. While these chemicals may be hazardous when inhaled or ingested, they are not likely to be absorbed through the scalp and cause any harm to your baby. That said, it's important for pregnant women considering this treatment to take extra precaution by wearing an appropriate protective mask that covers their nose and mouth while undergoing BKT. Additionally, pregnant women should avoid overexposure to heat from blow-drying and flat irons after the treatment in order to minimize further chemical exposure.