Ovulation Prediction Kits | Your Fertility Friend

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Ovulation prediction kits

What do ovulation prediction kits do?

If you’ve been attempting to get pregnant for a few months and not been successful, you might decide to use an ovulation prediction kit or fertility monitor to help identify the best time to have sex in order to conceive, which will aid in maximizing your chances of getting pregnant.

Ovulation prediction kits, also referred to as OPKs, are used to track ovulation. Rather than identifying when ovulation occurred in the past—like its most common counterpart, basal body temperature charting—OPKs predict ovulation before it occurs for more proactive conception planning.

How do ovulation prediction kits work?

There are two kinds of ovulation prediction kits—urine-based OPKs and salivary ferning kits.

Urine-based ovulation prediction kits

Though it’s always present in the urine in some levels, the luteinizing hormone increase 24–48 hours before ovulation. This increase in luteinizing hormone is what triggers the egg to be released from one of your ovaries, making it one of the key signs of ovulation. This is the most fertile time of your cycle and the moment both types of OPKs aim to identify.

Urine-based ovulation prediction kits test your urine for an increased level of luteinizing hormone, which happens most often within a day and a half before you ovulate.

While a small amount of luteinizing hormone is always present in the urine, this level will rise by about two to five-fold before you ovulate. A urine-based OPK test stick most often yields a positive result about 24–48 hours before an egg is released.

To maximize your chance of conceiving, you would plan to have sex or be inseminated during that window.

Urine based OPKs come with 5–20 days worth of test strips. Each day, you place a test stick under your urine stream or dip it into a collected urine sample in a cup (it cannot be diluted).

Your result will be indicated by colored stripes appearing on the test strip, which predict if a luteinizing hormone surge is happening.

Salivary ferning kits

Salivary ferning kits assist you in knowing when ovulation is coming by measuring changes in your saliva that correspond with your cycle.

Caused by rising estrogen levels, the salt content of your saliva increases before ovulation. If saliva is at a salt level indicating ovulation, you may be able to identify it by making out a ferning pattern in a drop of saliva placed on a glass slide under a microscope.

This pattern should mean you ovulate within the next few days, though ferning patterns are sometimes seen up to two days following ovulation.

To test with a salivary ferning kit, you’ll use your finger or lick the slide to transfer a little bit of your saliva onto the slide. Do so in the morning before you’ve had any food or drink.

Ensure the sample does not contain any air bubbles. After you’ve waited for the saliva to dry, you’ll use a microscope to check for ferning patterns.

What are the advantages and disadvantages of ovulation prediction kits?
OPKs are a widely used tool in the pursuit to pregnancy. Like with most tools like this, there are pros and cons to using them.

Some of the advantages of ovulation prediction kits are that they are convenient, non-invasive, widely available and easy to use. Some disadvantages include not working with certain fertility drugs and not working consistently for women over 40.

Are ovulation prediction tests right for you?

Due to their relatively low cost and minimal invasiveness, OPKs are generally a good option for those trying to conceive. Ovulation prediction kits do not work well for women with polycystic ovarian syndrome or women who are nearing menopause (over 40).

How accurate are ovulation prediction kits?

Urine-based ovulation prediction kits are more accurate than their saliva ferning counterparts, but neither is foolproof.

You’re most likely to get an accurate result by carefully following the kit’s instructions, testing at the same time each day and reading the results within the specified timing window.

Salivary ferning tests are less accurate because a ferning pattern can emerge up to six days before ovulation and at various other points in the menstrual cycle when the fertility window may be closed.

These tests are also more difficult to read. If your eyesight is not great, you may want to avoid these kind of OPKs.

OPKs are not accurate for women with polycystic ovarian syndrome or women who are nearing menopause.

Can ovulation prediction kits be wrong?

Ovulation kits can be wrong, both in detecting ovulation when it is not actually imminent and indicating ovulation is not imminent when it in fact is.

How much are ovulation prediction kits?

Urine-based ovulation prediction kits costs between $20 and $50, which includes five to ten test strips. There is not a lot of quality variance among brands, so you should pick the kit with the most strips for your dollar.

As soon as your get a positive result during your cycle, you should stop testing and save leftover sticks for the following month, assuming you do not conceive.

Though less accurate, salivary ferning kits are more affordable. It costs about $30 for the microscope and slide, which can be used over and over again. It’s recommended to replace the kit after about two years.

Where can you buy an ovulation prediction kit?

Ovulation predication kits are widely available online and wherever pharmacy products are sold.

When should you start testing for ovulation?

Both types of kits have different testing cycles. Carefully read and follow the instruction on whichever ovulation prediction kit you choose. Some OPKs suggest you start testing 18 days before you expect to start your period.

If you have a 28–day cycle, you’ve start testing on the tenth day after your last period started. From there, you test until you get a positive result.

When is the best time to take an ovulation prediction test?

Try to collect your urine or saliva sample at the same time each day and consult the instructions in your kit for specific guidelines on the best timing for testing.

Avoid drinking a lot of water before urine-based OPK tests. Too much water may dilute the urine sample and make it difficult to get an accurate result. You should read your results within ten minutes.

Positive results will not disappear but a non-surge day result may trigger the display of a second color stripe that can be misleading.

How many times a day should you take an ovulation prediction test?

OPKs should be tested once per day, at the same time each day. Some woman may need to test twice per day as their luteinizing hormone surge may only last ten hours, instead of the normal 12+.

Why should you not use first morning urine?

Some test kits require the use of afternoon urine in pursuit of a more accurate test result as the luteinizing hormone surge happens most often in the afternoon. That being said, you should always consult your kits instructions as some kits require the use of first morning urine to test.

When should you start testing for ovulation after your period?

Ovulation occurs about 14 days before the start of your period. Based on a 28–day normal cycle, you should begin ovulation predication kit testing ten days after the start of your last period.

When should you test for ovulation with irregular periods?

Identifying the suggested 18-day post-period testing start day can be difficult, especially for women with irregular periods. An alternate way to identify when to begin testing is waiting for a build up of fertile-level cervical mucus. Fertile-level cervical mucus has the consistency of egg whites.

Analyzing the results of an ovulation prediction test

Most urine-based tests take about five minutes to show a reaction (test result). After five minutes, you’ll examine the colored band on the test strip and compare it to the key in your kits instructions.

The color will indicate whether or not you are predicted to ovulate as soon as 12 hours following the test. All test strips include a control band that will show up to confirm the test strip is working. A band darker than the control indicates a positive result; a lighter band indicates a negative result.

If using a saliva OPK, compare what you see on your slide to the example slides included in the OPK’s instructions to know what to look for when identifying ferning patters in the dried saliva.

How many days will an ovulation test be positive?

Ovulation tests are not often positive for more than one day. However, there is also no need to continue testing once a positive result comes up.

Instead, you can save any extra strips for the next month of testing. Some women have found a correlation between multiple days of positive OPK testing and being pregnant. So multiple positive results may be an early sign of pregnancy.

How long after a positive ovulation test are you fertile?

You are most fertile about two days following a positive ovulation test result. Keep in mind that sperm can survive up to five days, so timing sex before and after ovulation is optimal for getting pregnant.

What should you do if you do not get a positive result?

If you test through a menstrual cycle and do not get a positive result there are a few things you should do. First, ensure you are following the testing instructions exactly, including guidelines on when to test, not to dilute urine or saliva, etc.

Another option if using a urine-based OPK is to start testing twice per day as some woman only experience a luteinizing hormone for ten hours instead of the normal 12+. Finally, if you continue months of testing with no positive results, consult your doctor as it may be a sign of a fertility issues.

Do certain drugs or medications affect an ovulation prediction test?

Fertility medications containing chorionic gondotropin (hCG) or luteinizing hormone, including the most commonly used fertility drug Clomid, can affect results of both kinds of ovulation prediction kits. Ask your doctor how these medications may affect OPK testing before using these tests.

Does birth control affect the results?

Hormonal birth control—the pill, ring, implants, etc.—stop the surge of luteinizing hormone and estrogen levels to prevent ovulation and will therefore affect results of an ovulation prediction kit.

Will the amounts of liquid you drink affect the result?

The amount of liquid you drink will affect the results of both types of ovulation prediction kits. Urine should not be overly diluted as if may cause a false negative test result. You should test saliva in the morning before consuming any food or drink.

Should you wait for a positive ovulation test to have sex?

You should have sex a few days before and after you think you’re ovulating. This will give you the highest chance of getting pregnant. Many couples opt to have sex every other day during this window as sperm can live up to five days.

Can ovulation prediction kits detect pregnancy?

Some woman have found a connection between a series of positive OPK results and being pregnant. While not fully proven, this may be an early sign of pregnancy.

Will ovulation tests be positive if pregnant?

Ovulation test results may come up positive when pregnant, but there are a number of other factors that could cause a surge in the luteinizing hormone, including ovulating later than usual or twice in one month.

Can you have a negative ovulation test but still ovulate?

Yes, OPKs may come up negative even if you have or are soon to ovulate.

Can you use ovulation prediction kits as a means of contraception?

Keep in mind that luteinizing hormone and estrogen levels may surge with or without ovulation, so it’s difficult to tell whether an egg has been released or not. OPKs should never be used to prevent pregnancy.