Following implantation, maternal and embryonic tissues combine and begin to form the placenta. Nutrients, oxygen, vitamins, and water in the mother’s blood stream pass through the placenta and umbilical cord to the embryo (then foetus); while carbon dioxide and other waste flows back to the mother. The placenta also produces hormones and maintains foetal temperature above the mother’s temperature. The best intensive care units found in modern hospitals hardly rival the placenta’s life-support capabilities. Nature at its finest!