Now is the time to quit smoking and drinking. Cigarette smoke contains various toxins that can damage your baby's body and cause congenital disabilities. Your baby is also sensitive even to small amounts of alcohol. Smoking or drinking during pregnancy is dangerous, especially during the first trimester when most organ systems are still developing. If you continue these habits, your chances of having congenital disabilities or miscarriages increases. Dr. Richard H. Schwarz, MD warns, "drinking heavily throughout pregnancy increases your risk of having a baby with fetal alcohol syndrome (FAS)."Consult with your doctor for advice on how to stop smoking. You might want to enroll in a program that helps you curb your desire for tobacco. Drinking any amount of alcohol is prohibited during the first trimester. Later in your pregnancy, it might be permissible to consume some alcohol as long as your doctor gives you the green light. However, never drink enough alcohol to make you drunk.