Earthworm is a hermaphrodite, allogeneic animal, but can also self-fertilize and reproduce if necessary. Because of an adult cockroach, there are both male and female reproductive organs. Despite this, due to the different maturity of the male and female reproductive organs, allogeneic fertilization is still required.

After the Earthworm mates, the oocysts are usually discharged 7 to 8 days apart. Due to the different types of mites, oocysts vary in size and shape, some are oval, and some are nearly spherical. The number of eggs contained in each oocyst and the number of hatched young Earthworms are different, some are only one, some are two, some are three to four, and some are more. The Earthworm, which is generally large, has larger oocysts, but the number of pups is small, often only one to two; the small sputum of the individual is small, but the number of pups is larger.