Within three to seven days after mating, American cockroach females produce egg cases known as oothecae. Each ootheca contains approximately 15 embryos. Adult females produce between six and 14 oothecae in one lifetime. After carrying the egg case on the tip of her abdomen for hours to a couple of days, the female deposits it in a hidden location. It adheres to the surface of its new location through the female’s saliva.
Under good conditions and optimal temperatures, immature cockroaches, also known as nymphs, will emerge within 24 to 38 days. As they grow, nymphs undergo metamorphosis. They do this by shedding their exoskeleton. By the time they are adult roaches, this will happen 10 to 13 times. At each molt, they appear more and more like adults. After undergoing their final molt, they are equipped with wings and reproductive capabilities. This process spans between six months to over a year. American cockroaches live for approximately one year.
The length of the American cockroach’s life is dependent upon environment, diet and other conditions. Favorable conditions lead to rapid population growth, while unfavorable conditions cause adult cockroaches to develop more slowly or to die prematurely.