Period Tracker – Menstrual Cycle Prediction & Fertility Window

Period tracker accuracy depends on cycle regularity. Cycles vary 21-35 days normally. Most women (65-70%) have accurate predictions within 2-3 days. Irregular cycles (PCOS, stress, hormonal changes) may be less predictable. Track 3+ cycles for best accuracy.

Normal cycle: 21-35 days. Average: 28 days. Period duration: 2-7 days. Regular cycles are typical but variation is normal. If cycle changes drastically (>7 days difference), consult a doctor.

Fertility window: 5 days before ovulation to 1 day after (6-day window). Ovulation typically occurs 14 days before next period. Sperm can survive 5 days; egg survives 12-24 hours after ovulation. Peak fertility: 2-3 days before ovulation.

Factors affecting cycle: stress, weight changes, exercise intensity, hormonal birth control, hormonal disorders (PCOS, thyroid), medications, travel, illness, caffeine, sleep. Large stressors can delay period by 1-2 weeks.

No. This tracks menstrual cycles only. For pregnancy detection, use pregnancy test (HCG). Pregnancy test accuracy: 99% after missed period. Some signs: missed period, nausea, breast tenderness, fatigue.

With hormonal contraception (pill, patch, ring): Cycle becomes artificial (no real ovulation). Tracker shows withdrawal bleeding predictability, not fertile window. For fertility awareness, use non-hormonal contraception.

PCOS (Polycystic Ovary Syndrome): Hormonal disorder causing irregular cycles (35-90+ days). Ovulation unpredictable. Standard trackers less accurate. Consult gynecologist for PCOS management.

Yes! Track: flow intensity, cramping, mood, energy, headaches. Helps identify patterns. Common PMS symptoms: bloating, mood changes, fatigue, food cravings 1-2 weeks before period.

Yes. Data is stored locally on your device. We don't collect, store, or send your cycle data to servers. No account required. Your privacy is protected.