Ovulation testing: how to predict ovulation


How the heck do you know when you’re ovulating?! Charting and body signs can be helpful, but when you really need to know so that you can get pregnant, ovulation testing might be the key. Knowing when you’re going to ovulate helps you make sure you don’t miss your fertile days. The body ever so wonderfully gives you a couple of simple ways to tell when it’s going to happen.

  1. Increase in cervical fluid. In the 3-5 days before ovulation, most women find that the fluid increases in quantity as well as gets thinner and clearer (often called EWCM or Egg White Cervical Mucus as that’s kind of what it looks/feels like!). This fertile fluid is often times felt at the opening of the vagina and you may even see wetness in your underwear. When you see this type of cervical fluid it means the body is gearing up to ovulate!
  2. Change in mood/body. Often times when we near ovulation we tend to be in a much better mood overall, full of energy, creativity, and even the libido spikes. Many women also find that their breasts seem fuller and they naturally are a few pounds lower than, say, during menstruation.
  3. LH surge happens. This one we can’t really see, but it’s easy to test for at home! Simple LH strips or OPKs (Ovulation Prediction Kits) can be purchased.
  4. Your saliva actually changes! By looking at the formation of specific crystallization patterns in dried saliva that occur at the time a woman would ovulate.

ovulation testing image of ovaries

What is the LH surge?

The luteinizing hormone (LH) is produced in the pituitary gland and secreted in small amounts throughout your cycle. When the egg reaches a certain size, usually a couple of days before ovulation, LH spikes and this surge is what triggers ovulation about 24-36 hours later.

If you are trying to get pregnant, this surge signals the best time to have sex as the egg is only viable for about 24 hours after it’s released. Why now instead of the day of ovulation? It’s simple really, the cervical fluid at this time actually keeps the sperm alive for up to 5 days and having sex in the days before you ovulate means that the sperm will be waiting for the egg as soon as it’s released!


How does ovulation testing work?

There are many kits and devices available on the market that can assist you in figuring out when you ovulate:

  • The cheapest option is LH strips, simple urine tests (available on Amazon). The upside is that they are cheap, the downside is that they can be harder to “read” (you have to figure out if the line is as dark as the control line) and many women have mixed results in the quality of strips.
  • Digital Ovulation Prediction Kits (OPKs) are a little pricier, but much like a home pregnancy test, they give you a simple smiley face when it detects a high enough level of LH in your urine. (available on Amazon)
  • Saliva tests (available on Amazon) are another option and these work by using a saliva sample under a magnifying glass, waiting for it to dry, and figuring out if you see “fern” type patterns in it. (side note – your cervical fluid also does this right before ovulation, but I have no idea if it works in this kit. 😉 )
  • Mira Fertility Tracker is a high tech way to not only figure out when you’re going to ovulate, but it also gives you a reading of the actual hormone level. Paired with a smartphone app for tracking other fertile signs, this system takes charting to a different level.


Tips for using LH strips, OPKs, and the Mira Tracker

  • Start testing about 4 or 5 days before you think you’ll ovulate. If you have a 28-day cycle, this means you’ll start testing every day 9 or 10 days after your period starts. Some women find it helpful to label the strip (noting the date and time) so that they can compare the darkness of the line each day. Others take a photo on their phone to refer back to.
  • If you have somewhat irregular cycles (but always less than 40 days), simply test every other day starting on the tenth day of your cycle. (Your cycle begins with the first day of your period). This way you’ll notice the surge if you ovulate earlier one specific month.
  • If you have wildly irregular cycles (common with PCOS and Hypothalamic Amenorrhea), testing for LH can be very tricky since many women can go months between periods. Your best bet is to begin testing when you notice cervical fluid changes, though it’s also common for women with irregular cycles to have LH spikes that don’t quite trigger ovulation (you’d find that you have multiple times of *almost* positive LH strips). You can also test every two to three days if you want to go through that many tests. High LH results are also common throughout the cycle for many with PCOS. If this is the case for you it’s probably better to find an alternative to figuring out when you might ovulate.
  • If you have a short cycle you can start testing every day starting on day 5 or 6.
  • Always test at about the same time every day and between 11am and 4pm. The LH surge usually happens in the morning but can take at least 90 minutes to show up in the urine. Some women do test with their first morning’s urine because it’s easier to do if you aren’t at home during the day, but it can produce false negatives in some. Using your second urine of the day, a few hours after you wake up produces the most accurate results so simply pee when you get up, wait four hours and then test it the next time you go to the bathroom!
  • Don’t pee for approximately 4 hours before you test. Go ahead and drink some fluids during this time, but not so much that you’ll be uncomfortable waiting for a few hours! Too many fluids can dilute the urine and give a false negative.
  • Stop testing once you get a positive result. It’s common to continue getting positives, even later in your cycle and the first one is all we’re concerned with! As soon as it’s positive you’ll know ovulation is happening soon, most often the next day and sometimes two days later. If you’re looking to get pregnant it’s best to have sex the day of the positive test and the following two days. If low sperm count, low testosterone, erectile dysfunction, painful sex, or work schedules make that difficult you’ll want to most importantly be intimate about 12 hours after the test is positive.
  • If you go more than two cycles without finding your surge, try testing 2-3 times a day (first thing int he morning, four hours later, and then four hours later). Some women find that their surges are quite short and they miss it!


Can you use LH testing for preventing pregnancy?

Many try and many end up pregnant. 😉

The thing is if you’re looking to prevent pregnancy the LH surge happens after the cervical fluid begins to change. It’s very possible that you can get pregnant from sperm that have been waiting 5 days before ovulation. The LH surge happens only a day or two before ovulation, so if you wait to abstain from sex until you see a positive surge, it will be too late.

Donielle Baker

Donielle Baker

owner and editor of Natural Fertility and Wellness at Natural Fertility and Wellness
I believe women can learn how to heal their bodies & balance their hormones through natural methods. An advocate for natural health, I have a passion for nourishing/real food nutrition and natural living. My personal background includes both infertility and miscarriage and I started Natural Fertility and Wellness in 2008 in order to share all of the information I found helpful in my journey to heal from PCOS and overcome infertility.
Donielle Baker
Donielle Baker
Donielle Baker
Many of the links on this site are affiliate links, which mean that the owner of the site may earn a small commission from your purchase through the company. We will not recommend a company that we do not purchase from ourselves and we thank you for your support. No contributor or author on this site is a medical doctor and the statements made here have not been approved by the Food and Drug Administration. These statements are not intended to diagnose, treat or cure or prevent any disease. This notice is required by the Federal Food, Drug and Cosmetic Act. Read our privacy policy and full disclosure here.


Fix your fertility naturally

Fix Your Fertility ebook
empowered charting ebook