Which is the Best Ovulation Predictor Kit Available - What are OPKs and How Do OPKs Work

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Trying to conceive is a stressful time, made even more stressful by the narrow window of opportunity in each menstrual cycle, otherwise known as ovulation. Miss that window of fertility when the egg is released and it’s the beginning of another game of hurry up and wait.

You may not be able to turn that clock back, but you can try to determine ovulation before it happens. Although there are physical signs of impending ovulation, they are sometimes unreliable and too subtle to notice. Identifying the hormonal changes that cause the release of the egg are more precise, and luckily for those trying to conceive, science has created a way to detect these changes to help increase the likelihood of a pregnancy. The best ovulation predictor kit, more commonly referred to in the trying-to-conceive-crowd as OPK, can help pinpoint ovulation for greater pregnancy success.

How Do OPKs Work?

OPKs work by measuring the amount of LH, or Luteinizing Hormone, in your system by way of your urine. LH is the hormone responsible for triggering the release of an egg during ovulation. Although LH is present in your system at all times, before ovulation it surges, which registers on an OPK as a positive result. Ovulation typically takes place from 24 to 48 hours after this surge, which gives you time to plan intercourse accordingly.

How Do I Use OPKs?

Regardless of the brand or design, all OPKs work the same way. One end of the testing stick is a handhold, while the other end is a “wick” of sorts that absorbs your urine. The stick contains chemicals that react when certain hormones are present. The OPK provides best results using a concentrated sample of urine, typically the first urine after you wake up. A control line will appear first, with a second line darkening within a few minutes. The darker the second line, the more LH is in your urine, and the closer you are to ovulation.

The Best Automated Ovulation Predictor Kit

Clearblue Easy Fertility Monitor

The Clearblue Easy Fertility Monitor is an OPK that takes the guesswork out of testing. It is a small machine that reads testing sticks and gives a clear indication on its LCD screen on the user’s fertility on any particular day – either low, high or peak. Low fertility means that there is little chance of conceiving, high fertility means the LH surge is near and there is a higher probability of conception, and peak fertility is the best chance at conceiving because ovulation is at hand.

The advantage of the Clearblue Easy Fertility Monitor is that it not only identifies the time of ovulation but the days of high fertility leading up to it. This gives you up to six additional days of advanced warning to maximize your chance of conceiving. The Monitor can also “learn” your cycle by storing data about your personal hormonal patterns, thereby giving a more accurate reading the longer you use it.

The Monitor uses specialized OPK sticks that are inserted into the bottom of the machine after testing. These come boxes of 30, which can last you numerous cycles, depending upon how many sticks the Monitor needs in any given cycle to detect ovulation.


  • Takes the guesswork out of reading OPK sticks
  • Easy to use
  • Clear, easy to read display
  • Shows up to 6 additional days of high fertility
  • Clean and sanitary – the sticks have caps that cover the urine dipped end
  • Tells you when to test for pregnancy


  • More expensive than other OPKs
  • Initial setup can be time consuming
  • Can take a few cycles to get to “know” you and your natural hormonal cycle
  • Not recommended for women with cycles shorter than 21 days or longer than 42 days
  • Replacement sticks can get costly

Bottom Line:

For women with predictable cycles and no other fertility problems, the Clearblue Easy Fertility Monitor may be all that’s needed to help hurry along the process of conceiving. You don’t waste time or fertility by trying to compare lines on the test sticks, the machine reads them and tells you how fertile you are in minutes. The additional fertile days are also helpful to have forewarning of upcoming ovulation.

The Best Manual Ovulation Predictor Kit

Clearblue Easy Ovulation Combination Pack

The Clearblue Easy Ovulation Combination Pack provides testing supplies for ovulation and pregnancy. In the box you’ll find seven ovulation sticks to detect impending release of the egg, plus a digital pregnancy test to let you know clearly – you’ll see “pregnant” appear on its little screen - if you successfully caught it.


  • Easy use
  • Fast results
  • Higher sensitivity to LH than most other OPKs


  • Easy to misinterpret results
  • Can be expensive if you have longer than average cycles

Bottom Line:

While seven OPKs may seem like just the right amount, you have to have a good idea of when you’re going to ovulate in the first place, otherwise you may be testing way too soon or too late. For women who have average length cycles, this shouldn’t be a problem, and the added bonus of a pregnancy test – a digital one, no less! - is convenient.

The Best Budget Ovulation Predictor Kit

Early-Pregnancy-Tests.com Ovulation Test Strips

The average menstrual cycle is 28 days, but very few women actually have a cycle of this length. Sometimes it’s shorter, sometimes it can be much longer. If your cycles don’t fit within the accepted “normal” range, you may find it expensive to use the store-bought OPKs. This is where Early-Pregnancy-Tests.com comes in.

Early-Pregnancy-Tests.com is a website specializing in affordable testing supplies for those trying to conceive. They sell OPKs, pregnancy tests, fertility supplements, and other fertility aids at inexpensive prices. Buying in bulk reduces the cost per piece, so you can test daily to catch the LH surge. The strips are just as sensitive as the more expensive, store-bought brands, so you won’t sacrifice quality for affordability.


  • Affordable
  • Easy to use
  • Order as many as you like in customizable packages
  • Online ordering
  • Home delivery
  • Test as often as you like without spending a fortune


  • Results may be difficult to interpret
  • Shipping Costs
  • Additional delivery time necessary

Bottom Line:

An affordable option for women with long, unpredictable cycles, Early-Pregnancy-Tests.com OPKs are just as accurate as the name brands without the name brand price. These tests allow you to test numerous times during the day if you wish, as your LH surge may occur later in the day and a morning testing wouldn’t have caught it. Ordering online and receiving the tests right in your mailbox also help keep your privacy in your time trying to conceive.


Even with proper use of OPKs, it may take time to conceive. OPKs help to narrow down your peak fertility, but even the best, most sensitive one on the market cannot guarantee you will get pregnant. Keep track of your cycles and health, and if you have any doubts or concerns about your fertility, speak with your GYN-OB.


AmericanPregnancy.org: Ovulation Kits & Fertility Monitors - www.americanpregnancy.org/gettingpregnant/ovulationkits.html

ConsumerResearch.com: Ovulation Predictor Kits - Reviews - www.consumersearch.com/ovulation-predictor-kits

ClearBlueEasy.com: ClearBlue Easy Fertility Monitor - www.clearblueeasy.com/clearblue-easy-fertility-monitor.php

ClearblueEasy.com: Clearblue Easy Ovulation Combination Pack - www.clearblueeasy.com/clearblue-easy-red-ovulation-test.php

Early-Pregnancy-Tests.com: Ovulation Tests – Test Strip Format - www.early-pregnancy-tests.com/pacof3ovtess.html