After around 5-7 weeks, the nymph will be an adult bed bug. Finding a large number of adult bed bugs can mean that the infestation has been there for a while. It takes about ten days for an egg to hatch, so fully developed bed bugs mean you've likely had an infestation for at least a few months. How to Kill Baby Bed Bugs
During its lifetime, a bed bug will go through the following stages (Starting from the top left, moving counterclockwise): Eggs (1mm). 1st stage nymph (1.5 mm). 2nd stage nymph (2 mm). 3rd stage nymph (2.5 mm). 4th stage nymph (3 mm). 5th stage nymph (4.5 mm). Unfed adult female.
Full-grown bed bugs move relatively slowly and measure between 4 to 5 mm. Homeowners sometimes have the misconception that bed bugs are too small to see with the naked eye. The nymphs may be small and difficult to see, but the adults are detectable with the naked eye and may be found in the cracks and crevices they use to hide.
Bed bug size changes at each life stage as shown below. A bed bug egg is 1/32" long. Adult bed bugs size that has not fed will be about 3/16". After feeding the body swells and grows in length to about 1/5" to 1/4".
Most people will find bed bug bites to be small and very itchy. These bites are often mistaken for something else such as eczema. It can be hard to diagnose bed bug bites due to this, especially if someone inflames their skin further by scratching the area. There are some signs that point more strongly to bed bugs over other types of bugs.
Bed bug eggs are small (around 0.1 inches, 2.5mm) long and appear white or semi-transparent, similar to a grain of uncooked white rice. They will be sticky to the touch and usually clustered together. You can also find shed egg shells after the infant bed bugs have hatched, but as these are very small