Understanding Your Menstrual Cycle
The menstrual cycle is the monthly process your body goes through to prepare for a potential pregnancy. Understanding the four phases can help you anticipate changes in energy, mood, and fertility throughout the month.
The Four Phases
Menstrual Phase (Days 1-5): Your period. The uterine lining sheds, causing bleeding that typically lasts 3-7 days. You may experience cramps, fatigue, and lower energy.
Follicular Phase (Days 6-13): Estrogen rises as follicles develop in the ovaries. Energy and mood typically improve. The uterine lining begins to rebuild.
Ovulatory Phase (Days 12-16): An egg is released from the ovary. This is your most fertile window. You may notice increased energy, clearer skin, and changes in cervical mucus.
Luteal Phase (Days 15-28): Progesterone rises to support a potential pregnancy. If the egg isn't fertilized, hormone levels drop, leading to PMS symptoms before the next period.
How to Use This Calculator
Enter your last period start date, average cycle length, and period duration. The calculator maps out your current and upcoming cycle phases so you can plan ahead and understand what your body is doing at each stage.