Premenstrual syndrome is a common condition that occurs in normally menstruating women.
Recent evidence has suggested that PMS may be associated with abnormalities in calcium hormones. Because bone mass and the prevention of bone loss depends in part on lifelong calcium intake, PMS may be an important marker for the development of osteoporosis. This study looks at calcium regulating hormones across the menstrual cycle. Participants will be screened for premenstrual symptoms with a daily self-assessment diary for approximately 3 months. During the 3 rd month, blood drawing will be performed at 8 time points.