Menstrual Cycle Phases:

• Follicular Phase: 1-5 days
• Follicular Phase: After Period - Fertile Period Start
• Fertile Period: 5 days before ovulation - 1 day after ovulation
• Luteal Phase: Fertile Period End - Next Period

Calculation:

• Ovulation: 1 day after the last period (cycle length - 14)
• Fertile Period Start: 5 days before ovulation
• Fertile Period End: 1 day after ovulation
• Next Period: 1 day after the last period (cycle length)