- In the industrialized world, approximately 12% of couples suffer from infertility. As a result of its collective political and historical experience, Israel boasts one of the world's most progressive fertility policies ranging from hormonal treatment to In Vitro Fertilization (IVF). Approximately 40% of the causes of infertility are attributed to the woman. Among the factors contributing to reduced fertility are endocrine factors, immune factors and mechanical factors. Studies have accumulated information regarding the contribution of psychological factors to infertility in women. Among the identified risk factors are depression, anxiety and stress-dependent changes like altered heart rate and increased blood cortisol levels. The hypothalamic-pituitary-adrenal axis (HPA) has been shown to be an important mediator of infertility, involved in the excretion of CRH, ACTH and cortisol, respectively. Data gathered in the literature suggests the involvement of the HPA axis on the hypothalamic-pituitary-gonadotropic axis (HPG). Specifically, changes in diurnal excretion patterns of cortisol have been shown to accompany mental stress and to mediate the down-regulation of the HPG axis. This impact could possibly involve inhibitory mechanisms at the pituitary level, by reducing the release of FSH and LH by GnRH. Furthermore, research has shown that the effect of cortisol on the HPG axis is dependent on the endocrine status of the ovary in its different stages within the menstrual cycle. From the studies presented in this review it can be hypothesized that stress can induce altered cortisol-excretion patterns along the menstrual cycle, which ultimately affect the hormonal profile in critical stages of the fertilization process.