Cockroaches lay their eggs in protected areas, close to food sources. When they hatch, the nymphs take care of themselves. Cockroaches prefer moist, warm environments. They can be found in bathrooms, kitchens, laundry rooms, and garbage bins. In some cases, you can find roach eggs hidden behind appliances or baseboards.
Cockroach eggs are dark brown and are 5 to 14 mm in size. They are small enough to be seen with naked eyes, but can be hidden in dark or concealed areas. The presence of eggs is an indication of a cockroach infestation. Eggs of the American cockroach measure less than a quarter-inch (5 mm). They have a keel, a weak spot on the side, and a ridge running down their length. The keel is the weak point of the egg, so it can break open when the nymphs hatch.
Cockroach eggs are enclosed in a protective casing called the ootheca. This ootheca protects the eggs from predators and the elements. They start out white, but harden to reddish brown or dark brown when they hatch. The size of roach eggs varies depending on the species.
American cockroach eggs are three-eighths of an inch in length, but they are larger than those of the German cockroach. They lay eggs every six weeks. One female German cockroach can produce between four and eight oothecae during her life.