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How Do Ovulation Predictor Kits & Ovulation Tests Work?

How Do Ovulation Predictor Kits & Ovulation Tests Work?

ovulation test

Every month women menstruate if they are not pregnant but before that, they go through ovulation. Ovulation is the process whereby a mature egg is released from the ovaries and this typically happens in the middle of a woman’s cycle. Now that we have established what ovulation is, it’s important to know why you should take an ovulation test. Ovulation tests and Ovulation Predictor Kits (opk) are important so that you can know when you are most fertile as a woman and also to help you plan if you want to conceive.

How Ovulation Tests Work

LH Surge Predictor, OPKs, Ovulation Predictor Kits are all different names for ovulation tests that can be performed at home and work by discovering the luteinizing hormone (LH) in a woman’s system. Shortly before ovulation, a woman’s LH will increase this is also known as LH surge. Ovulation test kits will recognize this sudden increase in LH and help you predict with accuracy when you will ovulate, These tests have been shown to be the least invasive way and most accurate way to detect ovulation

A positive result which means there is an LH surge shows that a woman will ovulate within the next 12 – 48 hours. It is important to note, however, that some tests can show false positives meaning there is no LH surge but the test indicates that there are high levels of LH in your system. This can happen if you are on fertility medications like Clomid and you test too early in your cycle.

How Ovulation Takes Place

At the beginning of your menstrual cycle, your body begins to produce FSH which is known as Follicle-stimulating hormone. The FSH facilitates the growth of follicles in the ovary. The follicle is what holds the ovum as it helps it grow to maturity. During the menstrual cycle when the luteinizing hormone has increased, and the follicle matured, the increase in LH is what leads to the opening of the follicle and the ovum is released into the fallopian tube. This is how ovulation occurs – when a mature ovum is released.

Small amounts of LH are usually present in the system during the entire menstrual cycle. When you are on your period, the Luteinizing hormone is usually very low. It is in the middle of the menstrual cycle that the LH shoots to its peak. The time which the LH increases is very short so a woman needs to be on the lookout. Even the time to test for LH is really important because, unlike pregnancy test which is best when done in the morning, an ovulation test should be done in the afternoon. After all, the LH is produced in the morning. The best times to test for the luteinizing hormone is from 10 am to 8 pm which is important to know if you are trying to conceive.

When is the Best Time to Start Testing for LH?

First, you have to find out the length of your menstrual cycle. A menstrual cycle comprises the first day you start your period to the day before the first day when you start your next period. The days in between are your menstrual cycle. So after finding out the days of your cycle by keeping track of the last three menstrual cycles, confirm with the table below when you can start an ovulation test. If your cycle length is not within 21 to 38 days, be sure to see a doctor.

ovulation and menstrual cycle table When to start testing with an Ovulation Predictor Kit (opk)

Taking an Ovulation Predictor Kits

Note that when you are about to take the OPK reducing liquid intake by approximately 2 hours before the test because the liquid will dilute the urine and prevent LH from being detected. Ovulation will take place 12 – 48 hours after the LH surge.

Ovulation Test Strip Instructions

  1. In a urine collection cup, collect a urine sample
  2. The urine and the sealed ovulation test pouch should be at room temperature which is 18-30 degrees before you can start the test
  3. After confirming the temperature and making sure it’s okay, remove the test strip from the pouch
  4. Dip the strip into the urine ensuring you do not pass the line written MAX
  5. Remove the strip after 15 seconds and place it on a flat surface and wait for the results

Interpreting your Ovulation Predictor Kit Test Results

You may have to wait for your results for up to 10 minutes but for positive results, it usually takes a shorter time even 40 seconds. If you see two visible lines, that’s the control line and the test line, if the test line is as dark or darker than the control line this is a positive result, you are likely to ovulate within 1-2 days.

If you are seeing two lines but one is faint that shows the control line and the test line, but the test line is faint that means the test is negative. Also if are just seeing one line then the test is a negative ovulation test

Also, you may get invalid results. if you can see no line at all or you are only seeing the test line, the test is invalid. Reasons can be either you pulled out the opk too early or you dipped the test strip beyond the MAX line. In this case, you have to repeat the test by using a new test and dipping the test to the max line.

positive ovulation strip test


When Should I Have Sex to Get Pregnant?

If you are looking forward to conceiving, the best time to have sexual intercourse is the day before your LH surge the day of LH surge and the three days after that. During this period, you will have a high chance of getting pregnant.

Using a Basal Body Temperature, also known as BBT, will help you know when ovulation has occurred as the ovulation thermometer works by telling you when an LH surge is done and not when you are experiencing an LH surge.

Can I use an Ovulation Test for contraception?

Do not use an ovulation test as a way of contraception because it’s not a reliable way of contraception using predictor kits this way has a 30 – 70% success rate. Go see a doctor who will help you to find out about the contraception methods and help you choose which one is ideal for you. OPKS are just for predicting when you will undergo ovulation to help increase your chances of getting pregnant.