Eli5: How come immunization shots that a woman gets earlier in her life don’t carry on/pass that immunity to her children when she gives birth?

Question

E.g. if a woman has a tetanus shot, why does the kid need one? If she has an mmr shot, why does her child need to get one? If the lady also has a shot immunizing herself from chicken-pox, why isn’t the child also immune from chicken-pox?

Wouldn’t the child be immune from the diseases/ sicknesses that the mother already got her shots for?

In: 108

Answer 1

Think of the protection the mother gets as expirable proteins. She can and does pass it out to her children but within a years time,those proteins are gone. So the developing child doesn’t get the protection for much long,however if the mother breastfeeds the child. The child will still receive protection from other kinds of expirable proteins in the breast milk.