What to Know About Bed Bugs’ Life Cycle

Updated: Oct. 20, 2023

Often invading homes undetected, learn the life cycle of bed bugs so you can effectively face and fight this persistent parasite head-on.

A huge nuisance pest that holes up in soft, warm and tiny spaces, the common adult bed bug (Cimex lectularius) is almost microscopic, about the size of an apple seed. It is distinguished by its brownish-yellow-to-rusty-red color, flat oval body and a beak-like mouth for piercing and sucking. Newly-hatched nymphs are a translucent light brown.

Feeding on the blood of animals and humans, a bed bug’s bite isn’t painful nor does it carry diseases. But it can leave behind unsightly red, itchy welts.

The Bed Bug Life Cycle

Here is an introduction to a bed bug’s life cycle — a process that takes less than 40 days to complete.

Egg Stage

About the size of a speck of dust, a bed bug egg looks like a grain of salt. Once a female lays her eggs, they hatch into nymphs in less than a week, depending on the room’s temperature.

Nymph/Baby Stage

For a nymph to mature into an adult bed bug, it must pass through five steps, shedding its exoskeleton at each point. This requires a meal of blood to move on to the next level. Under optimal conditions and with a consistent host on hand, a bed bug can fully develop in about a month.

Adult Stage

Once it reaches full maturity, an adult bed bug must feed regularly to reproduce. When they’re not dining on your blood, they hide in cracks, crevices and seams of upholstery.


Unique to the Cimicid family, bed bugs mate using a method called traumatic insemination. Without getting too graphic, basically the male stabs his reproductive organ through the female’s abdominal wall into her genitalia, called the Organ of Berlese. The sperm is released into the cavity where egg fertilization takes place.

Some females mate only once while other are stabbed multiple times. If the female runs out of sperm to fertilize her eggs, she has to mate again. However, she can easily mate with her offspring.

Bed Bug Lifespan

The lifespan of a bed bug, from beginning to end, is between 99 and 300 days.

Over her lifetime, a single female bed bug can lay hundreds of eggs into the seams of your mattresses and box springs. That’s why it’s so important for homeowners to catch the problem early. And given the stubbornness of this pest, it’s highly recommended that you get a professional exterminator involved before things spiral out of control.

Pro Tip: To find out if you have bed bugs, Ed Spicer of Pest Strategies says, “Depending on the size of the infestation, you might have to look very hard before you find the culprit and stop the spreading.”

How Long Do Bed Bugs Live Without a Host?

According to Dini M. Miller and Andrea Polanco of Virginia Tech’s Department of Entomology, a recent laboratory study showed that “on average, starved bed bugs (at any life stage) held at room temperature will die within 70 days. Most likely these bed bugs are dying of dehydration, rather than starving to death. Because bed bugs have no source of hydration other than their blood meal, dehydration is the greatest natural threat to their survival while living in the indoor environment.”

Without you or animals in the house, bed bugs can’t survive.