Once the worm has laid its eggs, it leaves the host. It is a common practice to plug the openings so the offspring can't get out after the hatching and matures directly inside the host, feeding on the slime left there by the adult worm.
Typically, a worm can produce six to ten eggs. They hatch very quickly, usually after a day or two. Collectors buy them for a high price, as they're seen as exotic, dangerous, hard to catch animals.