One egg, one window, one signal
Ovulation is the moment a mature follicle in the ovary ruptures and releases its egg into the fallopian tube. It happens once per cycle in most people, and the egg lives 12 to 24 hours.
Sperm can survive up to 5 days in the reproductive tract, which is why the 'fertile window' is around 6 days — the 5 days before ovulation and ovulation day itself.
How to tell you've ovulated
- Cervical mucus
- Around ovulation, mucus becomes clear, stretchy, and slippery — like raw egg white. After ovulation, progesterone dries it up.
- Basal body temperature
- A sustained rise of about 0.3°C for at least 3 days confirms ovulation happened — retrospectively.
- LH strips
- Test strips detect the LH surge, which happens 24–36 hours before ovulation. Useful for timing, not confirmation.
- Mid-cycle pain
- Some people feel a brief one-sided pelvic ache called mittelschmerz. It's not universal.
Ovulation matters even if you don't want a baby
Ovulation is the only way your body produces progesterone in meaningful amounts. No ovulation, no corpus luteum, no progesterone. Cycles without ovulation (anovulatory cycles) can still produce bleeding, but they leave estrogen unopposed — over time, this can increase risks like endometrial thickening.
This is why 'I still bleed monthly' isn't proof that everything is working. Regular bleeding without ovulation is common in PCOS, perimenopause, low body weight, and high stress states.
Self-check
Quick check
1. How long does the egg live after ovulation?