What I Want To Know About My Topic

I want to know why people abuse drugs and alcohol? Especially when they are holding another persons life in their hands. Secondly I would like to know if there is a certain amount of drugs or alcohol that you can take that will not affect the baby? If so how much? I also wonder what are the chances that your baby will be born with a birth defect if you use these products? As well I  questioned, what age group of parents where problem occur in the most? And why? I was also curious as to what human behavior patterns among race and gender which revealed the most problems with birth defects. If so, why? I wonder which: drugs, alcohol, or stress, affects the fetus worst? Lastly I pondered, should people known as drug or alcohol abusers take classes to help improve their behavior before delivery? Then If these people refuse to have the proper classes should they have the right to keep their own infant; Even though, they have proven to be irresponsible?