Yup. Male seahorses get pregnant, well sort of. They obviously don't have a uterus. Instead they have this internal pouch thing. The female lays the eggs inside of the the male with an ovipositor (essentially an elongated vagina that looks like a penis). They stick the the ovipositor inside the male and then lay the eggs inside him. He fertilizes the eggs inside his body and they carries the embryos to term. Nature is weird.

This has nothing to do with humans though. Lots of animals have sexes and reproduction systems the are completely alien to humans. Bearded dragons and many other reptiles have their sex determined by the temperature that their egg was incubated at. Many species of fish undergo full sex changes (like the actually become fully functioning members of the opposite sex, capable a producing gametes). Most slugs are true hermaphrodites. There are all-female lesbian clone lizards (They are all female and reproduce by cloning themselves, they have sex with each other anyway because why not). Nature is weird. However none of these animals are human.

What matters to how our society works is the way sex and reproduction work in humans, not lizards or seahorses or clownfish. It is interesting to learn about alternate systems just for the wonder of how much variation there is in life.