If you are pregnant and smoke marijuana, it crosses the placenta to your baby. Marijuana, like cigarette smoke, contains toxins that stop your baby from getting the proper supply of oxygen that he or she needs to grow.

Studies of marijuana effect on the unborn babies are inconclusive because many women who smoke marijuana also use tobacco and alcohol. Smoking marijuana increases the levels of carbon monoxide and carbon dioxide in the blood, which reduces the oxygen supply to the baby.

Smoking marijuana during pregnancy increases

• Miscarriage
• Low birth-weight
• Premature births
• Developmental delays
• Behavioral and learning problems

I smoked marijuana before I knew I was pregnant, Would it hurt my baby:

"occasional use of marijuana during the first trimester is unlikely to cause birth defects."

However once you are aware that you are pregnant, you should stop smoking. On doing this the chance of harming your baby will be less.