Sex differences in anxiety and depression are significant in mood and anxiety disorders, offering insights into the mechanisms of onset and maintenance of affective disturbances in both men and women. These differences arise from variations in brain structure, function, stress responsivity, reproductive hormones, and social experiences. The review explores clinical aspects of sex differences in affective disorders, including developmental stages and reproductive events. Biological, cultural, and experiential factors influence the phenomenology of mood and anxiety disorders. Developmental events, such as prenatal and postnatal exposures, play a critical role in shaping sex differences. Prenatal exposure to sex hormones influences brain development and behavior, with implications for later mental health. Postnatal factors, including childhood abuse and social support, also contribute to sex differences in anxiety and depression. Hormonal fluctuations during the menstrual cycle, pregnancy, and menopause affect women's vulnerability to mood and anxiety disorders. Sex differences in mood disorders, such as major depression, bipolar disorder, and seasonal affective disorder, are evident in symptom presentation, prevalence, and course. Women experience higher rates of depression and anxiety disorders, with distinct symptom patterns and comorbidities. Hormonal changes, particularly during the menstrual cycle and perimenopause, influence the severity and course of these disorders. Anxiety disorders, including post-traumatic stress disorder, obsessive-compulsive disorder, panic disorder, generalized anxiety disorder, and social anxiety disorder, also exhibit sex differences. Women are more likely to experience symptoms of these disorders, with hormonal fluctuations affecting symptom expression. The review highlights the complex interplay of biological, cultural, and environmental factors in shaping sex differences in anxiety and depression. While some sex differences may be biologically determined, cultural and environmental influences also play a significant role. Understanding these differences is crucial for developing effective treatments and interventions for both men and women.Sex differences in anxiety and depression are significant in mood and anxiety disorders, offering insights into the mechanisms of onset and maintenance of affective disturbances in both men and women. These differences arise from variations in brain structure, function, stress responsivity, reproductive hormones, and social experiences. The review explores clinical aspects of sex differences in affective disorders, including developmental stages and reproductive events. Biological, cultural, and experiential factors influence the phenomenology of mood and anxiety disorders. Developmental events, such as prenatal and postnatal exposures, play a critical role in shaping sex differences. Prenatal exposure to sex hormones influences brain development and behavior, with implications for later mental health. Postnatal factors, including childhood abuse and social support, also contribute to sex differences in anxiety and depression. Hormonal fluctuations during the menstrual cycle, pregnancy, and menopause affect women's vulnerability to mood and anxiety disorders. Sex differences in mood disorders, such as major depression, bipolar disorder, and seasonal affective disorder, are evident in symptom presentation, prevalence, and course. Women experience higher rates of depression and anxiety disorders, with distinct symptom patterns and comorbidities. Hormonal changes, particularly during the menstrual cycle and perimenopause, influence the severity and course of these disorders. Anxiety disorders, including post-traumatic stress disorder, obsessive-compulsive disorder, panic disorder, generalized anxiety disorder, and social anxiety disorder, also exhibit sex differences. Women are more likely to experience symptoms of these disorders, with hormonal fluctuations affecting symptom expression. The review highlights the complex interplay of biological, cultural, and environmental factors in shaping sex differences in anxiety and depression. While some sex differences may be biologically determined, cultural and environmental influences also play a significant role. Understanding these differences is crucial for developing effective treatments and interventions for both men and women.