Ralph Waldo Emerson (1803-1882), perhaps best known for his essay Self-Reliance (1841), was one of America's most influential thinkers and writers. After graduating from Harvard Divinity School, he followed nine generations of his family into the ministry but practiced for only a few years.
The first menstrual period is called  menarche .. The menstrual cycle is about four weeks long, starting on the first day of bleeding and ending when the next period begins. However, it can vary greatly when a girl first starts her period. It may skip months or come several times per month in the beginning.
If pregnancy doesnât take place, this cushioned lining is shed via vaginal bleeding. Menstrual periods last anywhere from two to seven days and the average cycle is once every 28 days, although it can vary. Anywhere between 24 and 35 days is considered a normal cycle.