Eumenorrhea is a healthy, normal menstrual period. People who have periods are said to have eumenorrhea when:

• Bleeding lasting 3-7 days,
• Occurs every 21-45 days
• Does not have any significant menstrual symptoms including pain and heavy bleeding (needing to change a pad or tampon every 1-2 hours or lasting more than 7 days.)

Eumenorrhea that occurs alongside normal ovulation provides the highest likelihood of conception when exposed to unprotected, appropriately timed sexual intercourse.