Ovulation calculator


Ovulation is the moment during a woman's menstrual cycle when the ovarian follicle releases the egg. This is the time of peak fertility for a woman. Predicting when a woman will ovulate by way of calendrical method or fertility charting is called ovulation calculation. This ovulation calculator provides approximate dates for predicting ovulation. There are several variables that can cause cycle irregularities. To ensure accuracy, ovulation calculator results may be used in conjunction with other predictive tools.
Other methods predict ovulation by detecting luteinizing hormone (LH). Just preceding ovulation, women experience an "LH surge" - a sudden, dramatic and brief rise in the level of luteinizing hormone. Ovulation tests detect this LH surge, allowing women to accurately predict when they will ovulate. A positive result on an ovulation test means that the woman will most likely become fertile over the next three days - with peak fertility at 36 hours following the LH surge. Basal body temperature, changes in cervical fluid and fertility charting have also been used to detect ovulation, as has fertility charting, which helps predict
Note: The ovulation calculator cannot be used to reliably to prevent pregnancy.

Related Terms

Basal body temperature, calendrical method, conception, fallopian tube, family planning method, fertility, luteinizing hormone, menstrual cycle, menstruation, ovulation, pregnancy.

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In order to calculate your approximate ovulation time, answer the following questions:
When was the first day of your last period?
How many days are there in your cycle?
What is the length of your luteal phase? (If known)
Next period: Date of last period plus cycle length. (This varies from person to person, but the following calculations are based on a regular period, regardless of how many days.) Example: May 1 + 28 days per cycle = May 29.
Ovulation date: Next period minus luteal phase. Example: May 29 - 14 days (luteal phase) = May 15.
Range: If unsure about the length of your luteal phase, take the expected day of your next period and subtract 10 from it. This is the end of your fertility range. Example: May 29 - 10 days = May 19.
Then repeat and subtract 16 days to find out the beginning of your fertility range. Example: May 29 - 16 days = May 13
These are the range of dates that you are most likely to be ovulating. Example: May 13 through May 19.
Note: Every woman's body is different and these calculators can only be used as predictive methods, but may not be 100% accurate and thus should not be used to reliably prevent pregnancy.