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Best Ovulation Predictor Kit

If you’re trying to conceive, then one of the most important things you can do is identify the point in your menstrual cycle (and in the month) when you ovulate. You’re fertile for only a few days before you ovulate and at most a day afterwards, so identifying this key point in your body’s cycle makes getting pregnant much easier!

One of the options you have available is using an Ovulation Predictor Kit (often known as an OPK) to help pin down the date you ovulate, so today OvuSense is having a look at them to help you pick the best one.

How Do They Work?

One of the most popular things about OPKs is that they are very easy to use. The kits test your urine for a key hormone that indicates when you’re due to ovulate. It works very much like a pregnancy test, in that it’s simple to use and gives you a simple yes/no answer to the key question “Am I ovulating?”

When Do You Use Them?

Unlike some more demanding ovulation tests, popular OPKs only need to be used around the middle of your cycle. They need you to have some understanding of the regularity of your menstrual cycle, so you can pick out a window around the time you might be ovulating, and use the kit to narrow it down.

As well as specifying when in the month you need to use your OPK, there’s conflicting advice for when in the day they give the best result! Some people say first thing in the morning gives you your best chance at an accurate result, and others, equally authoritative advise that the hormone the kits test for won’t appear in your urine until later in the afternoon. This ambiguity is one of the things that makes them more difficult to use.


There are drawbacks to any OPK, whichever one you choose.

To begin with, if you have naturally high or low levels of the hormone it checks for, both false positives and false negatives will be a problem. This makes it hard to pin that vital window for fertility when you’re actually ovulating.

Also, if you’re suffering from any kind of health condition that makes your menstrual cycle irregular, much longer than average, or even causes you to skip ovulation sometimes then identifying even when to use an OPK becomes as much a challenge as getting an accurate result from it.

The Best OPK

Ultimately, it’s hard for OvuSense to recommend hormone-based Ovulation Predictor Kits – when they can be confusing to use or give unreliable results if you don’t fit the standard profile they’re built to.

We’d recommend tracking your basal body temperature with a system like OvuSense itself. Our sensors measure your body temperature overnight, every night to establish what normal means for you, and then pick out the dips and spikes in temperature that signal ovulation, giving you plenty of time to capitalise on this information!

Find out more about core temperature technology and fertility here