What are the developmental stages in bed bugs?

Bed bug nymphs hatch from eggs, and go through 5 nymph stages before molting into adults.

The life cycle of bed bugs.

6 full blood meals are needed before last stage.

Each of the five nymph stages can only moult into the next stage and into adults after a proper blood meal.

Females need blood to start and continue egg laying and males to produce sperm and seminal fluid.