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How do ovulation predictor kits work and are they even effective?


Ovulation tests work by detecting the level of luteinizing hormone (LH) to determine the best time for conception. Ovulation tests are 99% effective for detecting LH levels. This is important because LH levels typically peak 24 to 36 hours prior to ovulation, and by knowing when your LH levels are highest, you can predict when you will ovulate. This will give you a two-day window of the best time to conceive.

Test kits include LH test sticks that detect the LH surges in your urine. Having intercourse 3 days after a positive test typically gives women the best chance of conception. Fertility monitors also work by detecting LH levels, but are able to track your body's LH levels over time, telling you when they rise and peak, rather than levels at a particular time. These monitors can identify as many as 6 fertile days, maximizing your chance at conception.

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