A female German cockroach carries an egg capsule containing around 40 eggs. She drops the capsule prior to hatching, though live births do occur in rare instances. Development from eggs to adults takes three to four months. Cockroaches live up to a year. The female may produce up to eight egg cases in a lifetime; in favorable conditions, she can produce 300 to 400 offspring. Other species of cockroaches, however, can produce an extremely high number of eggs in a lifetime; in some cases a female needs to be impregnated only once to be able to lay eggs for the rest of her life. Source: http://en.wikipedia.org/wiki/Cockroach#Eggs_and_egg_capsules