To add to the pregnancy idea lala5614 has.
Witch, elves, or some other character(s) could probably use eggs for something. Either trade for money and/or crafting something (like a special potion). Perhaps also a quest line of someone requesting them for some reason (important for another quest, the story, or not significant at all).
Other route you could take and/or in addition to above: "children." Since barbarian can only birth eggs, I doubt what comes out will be human. They can have uses. Like a minion to help fight, or just a creature that can be collected and kept as a pet in your home or other location with some interactions ranging from normal pet care to "play time

."
Bonus: the creature type that is spawned depends on who/what impregnated barbarian.