Explain the role of the placental during pregnancy including its importance in the transport of materials between mother and baby, and also how it acts as a barrier between them. Why it is strongly recommended that alcohol is not consumed during pregnancy?

The placenta allows for exchange of nutrients, gases, and waste between the fetus and mother. It acts as a barrier to prevent harmful substances in the mother’s blood from reaching the fetus, but it isn’t 100% effective. Alcohol can still reach the fetus and impair its development by weakening the nervous system or causing miscarriage.

Expert Answers

An illustration of the letter 'A' in a speech bubbles

The placenta acts as an interface between the mother and the fetus, allowing for the transfer of oxygen and nutrients from the mother to the fetus as well as the transfer of carbon dioxide and waste from the fetus to the mother. Gases, nutrients, and waste travel via the bloodstream—the placenta is essentially a system of blood vessels that connects the maternal and fetal circulatory systems. It is formed from fetal tissue and produces hormones necessary to maintain the pregnancy.

The placenta is protective to the fetus, because it acts as a barrier and can prevent the transport of some (not all) dangerous substances—essentially, the placenta’s job is to behave as a filter and make sure that the only materials that reach the fetus are those necessary for life, growth, and development.

However, alcohol is still a danger because it can cross the placental barrier and get into the fetus’s bloodstream. This is especially harmful if it occurs early in development when cells divide more rapidly. Alcohol is most likely to affect the embryonic nervous system. Fetal Alcohol Syndrome is a possible result – this disorder is characterized by neurological damage and impaired growth even after birth. Alcohol consumption during pregnancy can also cause miscarriage.

Approved by eNotes Editorial Team