Western diamondback rattlers do not lay eggs. They are ovoviviparous, meaning they give birth to live young after carrying the eggs inside their bodies. Females usually only reproduce once every two to three years and give birth to an average litter of nine or 10 offspring.
Rattlesnakes typically mate in the spring after emerging from hibernation. Females can store semen in their bodies, allowing fertilization of the ova to occur months after mating. Rattlers carry the eggs for six or seven months before giving birth.
Newborn rattlers are about 10 inches long and are completely independent of the mother. They remain in the vicinity of their birthplace for the first seven to 10 days of life before venturing out in search of food.