What is the primary function of the placenta for the fetus?

The primary function of the placenta for the fetus is indeed to deliver oxygen and nutrients from the mother. The placenta plays a crucial role in fetal development by facilitating the transfer of essential substances from the maternal blood supply to the fetus, which is critical for growth and metabolic processes. It allows oxygen, glucose, amino acids, and fatty acids to pass through while also facilitating the removal of carbon dioxide and metabolic waste products from the fetal circulation.

The placenta's structure enables this exchange to occur efficiently, with its large surface area and extensive vascular connections to both the mother and fetus. This is vital since the fetus relies completely on the mother for its nutritional needs and for oxygen, as it cannot breathe air before birth.

While the placenta does have additional roles, such as producing hormones that contribute to pregnancy maintenance and fetal development, those functions support but do not primarily define its role in nutrient and oxygen transfer. Additionally, while the placenta does provide some level of protection against pathogens, it is not a foolproof barrier, and certain infections can cross the placental barrier. Waste storage is not a primary function of the placenta, as the fetus typically disposes of waste through the mother's circulatory system via the placenta, rather than storing it.