Bed bug eggs are milky white in color and about 1 mm long, the size of 2 grains of salt. Females lay between one and five eggs per day and may lie up to 500 in one lifetime. Eggs hatch within two weeks and the nymph begins to feed immediately.
Young nymphs shed their skin as they grow and must pass through five molts to reach maturity. They appear similar to adult bed bugs, but are not yet sexually mature. Young nymphs are yellow-white in color and become red after eating, and more reddish-brown as they mature. At room temperature these nymphs become adults in five weeks. Nymphs must have at least one blood feeding for each molt.
Adult bed bugs often make feedings weekly. Usually a mature bed bug lives from four to six months, although this can be considerably longer in cool conditions where they can go extended amounts of time without food.