Nature
Male seahorses are the ones who get pregnant and give birth
Female seahorses deposit their eggs into a pouch on the male's body, and from there he takes over — fertilizing, aerating and nourishing the embryos through a placenta-like tissue for weeks. When labor begins, he pumps his tail and contracts the pouch until the fully formed young are pushed out into open water. It's one of the only true reversals of pregnancy in the animal kingdom.