Human impact on the environment. Human impact on the environment or anthropogenic impact on the environment includes impacts on biophysical environments, biodiversity, and other resources. The term anthropogenic designates an effect or object resulting from human activity.
Premenstrual Syndrome. A combination of distressing physical, psychologic, or behavioral changes that occur during the luteal phase of the menstrual cycle. Symptoms of PMS are diverse (such as pain, water-retention, anxiety, cravings, and depression) and they diminish markedly 2 or 3 days after the initiation of menses.
1 Signs and symptoms of premenstrual syndrome change with hormonal fluctuations and disappear with pregnancy and menopause.  Chemical changes in the brain. Fluctuations of serotonin, a brain chemical (neurotransmitter) that is thought to play a crucial role in mood states, could trigger PMS symptoms.