How does Diffusion happen in the Womb?

diffusion of oxygen between an embryo/infant in the womb and mother is done through the umbilical cord and the placenta. Tiny capillaries in the placenta are right next to the capillaries that are part of the infant. Oxygen diffuses between these two blood vessels, but the mothers blood and the baby's blood does not mix. Diffusion of oxygen only occurs. Nutrients are obtained through the umbilical cord through facilitated diffusion as nutrients p from the mother to child.