So the brain and the spinal cord, they also have a variety of different types of learning disabilities and physical disabilities. So alcohol, recreational drugs, medicinal drugs, smoking all these things are really bad not only for that mother, but these effects are amplified and are really bad for that developing fetus. Now, let's move on to pathogens. So by pathogens, we mean some type of agent that can infect the body as well as the fetus and basically cause harm to that developing fetus. So we have many different types of examples. For example, HIV.