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Do ovulation predictor kits (OPKs) work for everyone?


Before we get on to the question, let’s run through what ovulation is and what ovulation predictor kits are.

What is Ovulation?

The process by which one egg (or more) is released from your ovary every month is known as ovulation. Every month, around 15 to 20 eggs are matured in the ovary and out of them, the largest gets pushed out. This egg will then enter the fallopian tube and head towards the uterus. The trigger for this release of the egg is luteinizing hormone (LH). Although LH is present in your blood and urine, it increases rapidly around 24 to 48 hours before ovulation. This is known as the LH surge and is responsible for ovulation.

Once the egg is released, it can only live for 24 hours and therefore it has only 24 hours to be fertilized. However, sperm can last inside a woman under the right conditions for a period of up to 5 days. Therefore, timing sex to occur just before ovulation increases the chance of fertilizing that egg. Keeping track of when you will be ovulating is important for determining your fertile window, or best time to conceive, and this is where ovulation predictor kits become handy.

What is an Ovulation Predictor Kit?

Urine-based Ovulation predictor kits (OPK) test your urine for the luteinizing hormone surge. Since this happens one or 2 days before ovulation, this kit will help you to determine that you may ovulate. Remember they don’t detect ovulation, they just signal that it may happen for you within a day or two so that you can time sexual intercourse to help you conceive.

All you have to do is collect some urine into a cup and dip the OPK strip into the urine or directly hold the strip under as you urinate. The test card will indicate whether or not the LH surge is occurring by means of colored bands or symbols.

To maximize effectiveness, make sure that you take the test at the same time of the day. Also, do not drink a lot of water before taking this test because increased water intake may make your urine diluted and give false-negatives.

Do Ovulation Prediction Kits Work for Everyone?

No, ovulation prediction kits do not work for everyone. If you don’t have an LH surge strong enough to create a positive test line, then you may not see positive results at all. In such cases, a digital test may be useful.

OPKs may not work well for women with PCOS (polycystic ovary syndrome) as well. This is because women with PCOS have several LH surges during a month and therefore may see positive results for several days. These are false-positives and do not indicate that you are really ovulating.

Ovulation kits may not work for those who have irregular menstrual cycles as well. OPKs work best for those who have regular monthly periods.

It is also important to remember that when waiting for an LH surge, it is possible to miss days of the fertile window.

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