Alcohol, nicotine, caffeine, drugs and viruses, such as rubella and listeria, can enter a fetus's blood from the mother's through the ___________ and possibly affect the fetus's growth and development.
I would say the answer would be through the placenta. At this part, substances that are harmful or not are transferred in and out this membrane . That is why pregnant women are not allowed to drink and eat various foods and drinks that could be harmful to the baby. It may cause abnormalities or death.
