Neuroendocrine interactions of the stress and reproductive axes

•Stress typically inhibits reproductive parameters via components of the HPA axis.•In certain conditions, stress can be stimulatory to the reproductive system.•Stress response is modulated by sex steroid hormones.•Components of the HPA axis act at multiple targets in the HPG axis. Reproduction is controlled by a sequential regulation of the hypothalamo-pituitary–gonadal (HPG) axis. The HPG axis integrates multiple inputs to maintain proper reproductive functions. It has long been demonstrated that stress alters fertility. Nonetheless, the central mechanisms of how stress interacts with the reproductive system are not fully understood. One of the major pathways that is activated during the stress response is the hypothalamo-pituitary-adrenal (HPA) axis. In this review, we discuss several aspects of the interactions between these two neuroendocrine systems to offer insights to mechanisms of how the HPA and HPG axes interact. We have also included discussions of other systems, for example GABA-producing neurons, where they are informative to the overall picture of stress effects on reproduction.