Alcohol is a teratogen (toxin)
Alcohol interrupts or changes the normal development of a fetus, including the brain and other organs at any stage during pregnancy. Examples of other toxins that can harm a developing baby include radiation, mercury, lead and medicines such as thalidomide and anti-epileptic drugs.
Alcohol crosses the placenta
The baby is exposed to the same blood level of alcohol as the mother. Because the liver of the developing baby is not fully formed until late in pregnancy. This means the baby has the same, or possibly even higher blood alcohol content as the mother and it remains at that level longer.
No amount of alcohol at any time during pregnancy is guaranteed to be completely 'safe' or 'risk free' for the developing baby. We know that any alcohol consumption changes some biolgical processes in the cells of the mother and baby.
The actual risk of harm is hard to predict and is different for everyone. This is because other factors such as:
- general health and medical conditions
- levels of stress
- other drug use
- body composition (percentage of fat, muscle, water, bone)
also influence how alcohol is metabolised and therefore the risk of harm to the developing baby.
While we know that the risk for the developing baby is highest when drinking heavily throughout pregnancy, we can't pinpoint the specific amount where harm starts. Because of this it is best not to drink alcohol at all during pregnancy.