1. Getting pregnant
  2. Trying to conceive
  3. Ovulation tracking

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Ovulation Kit: How to Choose the Right Fertility Predictor and Use It for Maximum Accuracy

There is an increasing demand for effective control over fertility monitoring. Some women spend a lot of time understanding their ovulation to become pregnant. Predicting ovulation is a helpful key if you are trying to become pregnant. Ovulation predictor test kits predict the release of an egg within hours or days. Your egg only is only able to be fertilized twelve to twenty-four hours after you ovulate. In this article we'll focus on how to use ovulation kits to monitor your fertility if you're planning for a baby.

An ovulation kit detects the Luteinizing hormone (LH) surge that happens before ovulation. It is one of the easiest ways to find out the best time to have sex in order to increase your chances of getting pregnant. The tests tell you when your body is entering the peak baby-making phase of its monthly cycle. Medical technology advancements have made the ovulation predictor test kits one of the most reliable options. 

An ovulation kit is also known as ovulation predictor kit (OPK). The kit detects the surge in LH in the urine and tells you when you may be approaching ovulation. The test predicts ovulation based on LH concentrations in urine. Another method of ovulation detection is viewing the changes in saliva. 

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The kit has two lines. One line is the control line. It will tell you that the kit is working. The second line is the test line. LH is surging when the test line is similar in color or darker than the control line.

Some of the recommended ovulation kits are:

Fertility monitors are electronic devices tracking the LH and estrogen levels in urine. Their main purpose is to predict peak fertility time in a woman’s ovarian cycle. The monitors serve as important tools for improving your probabilities of getting pregnant. The device records your ovulation cycle and helps identify your most fertile days. It increases your chances of conceiving.

Before you begin

Calculate when to start making use of the chart. First, calculate the period of your average cycle. Your cycle length is the amount of days between the first day of one period and the first day of the next one.

NOTE: If you have irregular cycles, use your shortest cycle length to decide when to do the test. 

  • Do not collect your wee early morning as it is in concentrated form and may give false results
  • Urinate into a sterile container
  • Take out the test card from the case.
  • Hold the test strip in a vertical position and ensure that the arrows point downward
  • Dip the strip into the urine approximately 1/4 inch and hold it there for at least five seconds (dipping the strip for longer will not produce false results)
  • Don’t dip past the stop line
  • Take out the strip and lay it down flat
  • Read the results after 5-10 minutes (follow the instructions on the package)
  • If a control line is not visible, the test is invalid
  • If the test line is like the control line or darker in color compared to the control line, your LH has surged. Your ovulation will begin in the next 34 to 36 hours
  • Once LH has surged, there is no need to continue testing
  • If two lines are visible but the test line is not as dark as the control line, your LH level has not surged.

It’s quite an easy method for figuring out the fertility window. When a woman is about to ovulate, her saliva starts to form a pattern that resembles the leaves of the fern. This pattern is a result of an increase in the level of salt and estrogen.

The instructions to do the saliva fertility test are:

  • Smear saliva onto a removable glass slide supplied with the test device
  • Allow it to dry and then observe the slide through a microscope
  • Dots or circle shapes appear in normal. But close to ovulation, a fern-like pattern is visible. A positive test tells you that you may be near the time of ovulation.

How do ovulation kits work? This is one of the most common questions of women planning for a baby and dealing with fertility isues. Here is the answer. 

An ovulation kit tests your wee (urine) sample to detect a surge in LH (luteinizing hormone) levels. While the LH is always present in your urine, it increases 34 — 36 hours before ovulation. These tests help you find out those days that act as an invaluable tool in your baby-making arsenal. One or two days before ovulation, your LH may surge up to five times the amount. The LH surge happens 34 — 36 hours before ovulation. This time is your most fertile window. Having intercourse on those particular days increases your chance of a successful conception.

First and foremost, make sure to follow all the instructions on the package of the ovulation kit you use. Here are the general instructions to give you a rough idea.

Urine-based ovulation predictor kit

For this test, collect your urine in a sterile container or place the stick under you as you wee. A certain color band will appear on the test stick. The test card could even display a positive sign indicating that the LH surge is occurring. The positive sign will confirm ovulation in the next twenty-four to thirty-six hours. Digital ovulation indicator kit uses a smiley face, to tell your most fertile days.

Some of the tips you can follow to use your ovulation detection kit properly are:

  • try to collect your urine sample at about the same time each day
  • do not test your urine as soon as you wake up
  • try to reduce the amount of fluids you drink for about 2 hours before you use the ovulation tracker kit
  • excessive fluids will dilute your urine, which will make it difficult to detect your LH surge
  • read the results on the test card within ten minutes. A positive result will not vanish. But some negative results after some time may display a faint second color band
  • throw the test stick once you have read the result. It is not meant for reuse

Saliva ovulation predictor kit

Saliva ovulation predictor kits are easy to use. Add a drop of saliva to the slide and let the sample dry. View the slide under the microscope. If ovulation is about to begin – a distinct fern-like pattern appears. This is visible under the power of the microscope. This fern-like pattern is a result of an increase in the level of salt and estrogen. The pattern begins to appear around three to five days before ovulation. 

The test allows you to predict peak fertility. Some of the tips you can follow to use your Saliva ovulation predictor kit are:

  • do the test in the morning when you wake up
  • do not eat, drink, smoke or brush teeth before the test
  • clean the slide or lens before using it
  • remove your glasses when viewing the slide under the microscope
  • remove the test slide by pulling it out of the casing
  • place a drop of saliva from beneath your tongue on the slide surface. Avoid creating air bubbles. 
  • allow it to dry for 5 minutes
  • look into the lens. Adjust the eyepiece and push the LED light button to see the test result
  • clean the lens after every use with a lens cleaner. The ovulation microscopes are reusable, discreet, and easy-to-use.

In the US, standard urine-based OPKs are priced around $30 for 10 sticks.  Most of the brands offer the same level of reliability, so choose the one that allows you to do more tests with the least amount of money. Digital Ovulation test kits are priced at $40 for one digital reader and 20 test sticks. A standard fertility monitor will cost $230 for one Fertility predictor and $65 for 30 test strips.

Are ovulation kits accurate? In fact, ovulation kits appear to be more accurate than calendar and temperature methods at predicting the most fertile days.

If used in a proper way, OPK provides 99% accurate forecast of your LH surge that precedes ovulation. But these tests are not able to confirm whether ovulation actually occurs a day or two later. Some women experience LH surge without releasing an egg, which is known as Luteinized Unruptured Follicle Syndrome (LUFS). Regular sex all through your cycle is the best way to increase your chances of conception.

Ovulation tests can be frustrating when you never get a positive result. There are several reasons for that. In some cases, you can yourself resolve the problems. But for some problems, you need a consultation with the doctor. Some of the reasons of negative ovulation test are:

LH surge happens 24-36 hours before ovulation. A lot of women who test for LH surge only test for a few days before the day that they expect ovulation to happen. Some women find this test ineffective and get negative ovulation test. This is because the LH surge is very tricky to predict. Sometimes it comes faster than planned. It is also possible that the LH surge may get over within 10 hours and you may miss it. If you do the test only once a day, you might actually miss the LH surge altogether.  Some doctors thus suggest doing the test twice a day.  By doing the test twice a day, a few days before ovulation and at least ten hours apart, you may pick up the LH surge.

LH surge happens at different times for different women. So, it is important that you should keep a track of your menstrual cycles. By keeping track of your cycles for at least 6 months, you will be able to identify a pattern. This would help you determine when ovulation should occur.

The third reason for negative ovulation test could be the inappropriate timings. LH often surges during the early afternoon hours, and you should do the test at around noon. The best time to carry out the ovulation test is between 11 am and 3 pm or between 5 pm and 10 pm.

It is possible that you are suffering from an ovulation disorder.

Possible causes of ovulation problems include:

  • anxiety
  • hypothalamus not secreting gonadotropin-releasing hormone
  • ovaries producing too little estrogen
  • pituitary gland producing too little LH or follicle-stimulating hormones
  • pituitary gland producing too much prolactin
  • blood sugar/diabetes
  • strenuous exercise
  • adrenal glands overproducing male hormones, testosterone, for example 
  • polycystic ovary syndrome (PCOS) that causes ovaries not to work
  • health issues, including cysts, tumors, or other masses
  • obesity or excessive weight loss  
  • drugs (estrogens and progestins)

It is good to consult your doctor if you feel there are issues with your ovulation pattern and the OPK’s are not helping you. 

Ovulation test kits are a boon for women who want to plan a baby. Monitoring your ovulation and fertility pattern is actually quite simple as there is an exact science to it, except of course for exceptional cases based on your medical history. A variety of options discussed above give women a great advantage to understand their cycle by helping to determine when ovulation is about to occur. Most of the test kits claim 98 to 99 percent accuracy. Choosing which ovulation test kit to use in the end becomes a personal decision.

The post is helpful for anyone who is looking into OPK’s. Ovulation test kits are the best choice if you are trying for your own little miracle. Don’t hesitate to consult your physician for any questions that will help let you identify your ovulation patterns, in case the test kits are not helpful to you.

Reviewed by Tahir Mahmood, Chair of Standards of Care European Board and College of Obstetrics and Gynaecology.

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