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Track your menstrual cycles, predict upcoming periods, fertile windows, and ovulation dates for multiple future cycles.
Cycle Prediction:
Next Period = Previous LMP + Cycle Length
Ovulation = Period Start + (Cycle Length - 14)
Fertile Window = Ovulation - 5 days to Ovulation + 1 day
Average cycle length: 21-35 days. Average period: 3-7 days.
A typical menstrual cycle ranges from 21 to 35 days, with most cycles averaging 28 days. The period (menstruation phase) typically lasts 3-7 days. Significant variation between cycles may warrant medical evaluation.
The menstrual cycle has four phases: menstruation (shedding of uterine lining), follicular phase (follicle development), ovulation (egg release), and luteal phase (preparation for potential pregnancy).
Irregular periods can be caused by stress, significant weight changes, excessive exercise, thyroid disorders, polycystic ovary syndrome (PCOS), perimenopause, or hormonal contraceptives. Consistently irregular cycles should be evaluated by a doctor.
It is unlikely but possible. If you have a short cycle (21-24 days), sperm from intercourse during your period may survive until ovulation. Pregnancy is most likely in the 3 days before and on ovulation day.
Use a period tracking app, record the first day of each period, note cycle length, and track secondary signs like basal body temperature and cervical mucus changes for the most accurate ovulation predictions.
Consult a healthcare provider if your cycle is regularly shorter than 21 days or longer than 35 days, if you miss 3+ consecutive periods, if periods last longer than 7 days, or if you experience extremely heavy bleeding or severe pain.