Flexi Says: The reproductive system works together with several other organ systems like the nervous, endocrine, excretory, and circulatory systems. The pituitary hormones stimulate the ovaries and testes to produce sex hormones which help in the maturation and functioning of the reproductive organs. These organs are themselves a part of the endocrine system. The endocrine system is in turn stimulated by the nervous system. The circulatory system carries the endocrine hormones to the target organs which are a part of the reproductive function.