the "go back to mom" mythology character?

[jellyfish_0920]

The character entented to go back to the mother's uterus, while the mother is asleeping, legs spread; however when the character came there, the mother awaked, hence the character is dead (or the mother? I can't remember)
Please tell me if there any trace can prove this stereotype story is from some ancient Mythology instead of my very own made up.
Thank you!

[Epona]

I vaguely remember a tale.

A woman had a baby. But the baby somehow became possessed or evil. The baby returned to the mother's uterus, and killed her from the inside out. He emerged from her corpse a grown man.

I don't remember where this myth is from, its just at the very edges of my memory. Maybe someone else knows where it might be from.