Pregnancy Health
Biology: Cambridge International GCSE Supplement, topic 16.4.7
Pregnancy Health
It is important that the foetus is connected to the mother's bloodstream through the placenta so it can get everything it needs. But, this means that any harmful substances in the mother's blood can easily reach the foetus.
Substance exchange
- The placenta provides the foetus with oxygen, nutrients for growth.
- It also removes excretory waste products such as carbon dioxide from the foetus.
- The placenta acts as barrier and can stop many (but not all) toxins and pathogens from passing from the mother's blood to the foetus.
Harmful substances
- Pregnant women are advised not to smoke or drink alcohol, because nicotine (in cigarettes) and alcohol can pass through the placenta into the blood of the foetus. This can seriously harm its development.
- Pregnant women are also told to avoid foods that are more likely to carry pathogens such as undercooked meat.
- The rubella virus is a pathogen can pass through the placenta and harm the foetus.
Test yourself on Pregnancy Health
Pregnant women are advised to not consume all but which of these?