Gestation is defined by Merriam-Webster as "the carrying of young in the uterus." Insects, unlike mammals, do not have a uterus and therefore do not typically have young which gestate. Some individuals may call the development of cockroaches in the eggs "gestation." As such, cockroach "gestation" begins when a female specimen creates an ootheca, or an egg case, which contains a number of eggs. Most species deposit this egg case in a safe, protective area, where it remains until it hatches. However, females of some species, such as German cockroaches, carry the ootheca attached to their abdomens until it hatches. Other species, like the Madagascar hissing cockroach, retain the ootheca inside their body until the nymphs are ready to hatch and give the illusion of live birth.
After hatching, nymphs are ghostly white and soft. Once their exoskeleton hardens they will darken and become their normal color. Cockroaches nymphs undergo a series of molts until they eventually become adults. Adults of many species can be distinguished from nymphs by their larger size and the presence of wings. However, a few species of cockroach, like the Madagascar hissing cockroach, lack wings even as adults.
If a homeowner is experiencing cockroaches invading their homes, it is advisable to contact a pest control professional. They can evaluate the home for attractants, entry points and likely harborage sites. The professional can partner with the customer to develop a customized solution to combat these unwelcome cockroach visitors.