Confirming ovulation, not just predicting it
Calendar math predicts; biomarkers confirm. Luteinizing hormone urine tests turn positive 24–36 hours before ovulation, and a sustained basal body temperature rise confirms it happened after the fact.
- • Cervical mucus turning clear and stretchy signals peak fertility.
- • Stress, illness, and travel commonly delay ovulation by days.
- • Track three cycles before drawing conclusions about your pattern.
FAQ
When am I most fertile?
The two days before ovulation and the day of ovulation carry the highest conception probability, though the window opens about five days earlier because sperm survive.
Can I use this as birth control?
No. Ovulation timing shifts with stress, illness, and travel, so calendar methods have high real-world failure rates. Use a clinically validated contraceptive method.
Do I always ovulate on day 14?
No. Day 14 only applies to a textbook 28-day cycle with a 14-day luteal phase. Counting back from your expected period is more accurate.
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Written by Sam Doshi and the RevenueLab editorial team. We don't sell the data feeds this tool is built on.
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