The reproductive system affects the body in several key ways: For females, it enables puberty and causes menstruation through hormones that stimulate the ovaries to release eggs every month. For males, hormones stimulate the testes to produce sperm and the main male hormone, testosterone. The reproductive system is made up of both internal and external organs that work together to enable procreation in both sexes - in females through egg production and in males through continuous sperm production.