Process: Nourishing the Fetus

The fetus is dependent on the mother for nourishment and oxygen. These substances are transferred from the mother’s blood to the fetus’s blood inside the placenta, an organ attached to the uterus and connected to the fetus by the umbilical cord. About 600 ml (1.1 pints) of maternal blood passes through the placenta every single minute, carrying a continuous supply of nutrients.

Blood vessels of the placenta

Inside the placenta, various substances are exchanged between the mother’s blood and that of the fetus through a thin membrane called the chorion. Oxygen, nutrients, and antibodies pass from the mother’s blood to the fetus’s blood, and waste products pass in the opposite direction.

Placental tissue

This magnified image of a section of placenta shows tissue from both the mother and the fetus. In the placenta, their blood circulations do not mix but are in very close proximity.

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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