Recognize the Signs of Ovulation With At-Home Predictor Kits

Content medically reviewed by Caitlin Pandolfo, MD

If you’re thinking about getting pregnant, tracking your menstrual cycle is important. Knowing your fertility window can help ensure you’re trying to conceive at the right time of the month. Over-the-counter ovulation tests are a common way to help track when you are likely to be most fertile, but they may not work as well for some women. Essentia Health has the information you need for tracking ovulation as part of your conception journey.

The Facts About Ovulation

Ovulation is the time during your menstrual cycle when your ovary releases an egg for possible fertilization. Most women experience menstruation once a month from adolescence until menopause. 

However, not all women experience regular or predictable ovulation. Hormonal birth control prevents ovulation, and medical conditions such as polycystic ovary syndrome (PCOS) can cause irregular ovulation.

Women who have a 28-day menstrual cycle usually ovulate between 11 and 14 days after the first day of their period. The fertile window is the six days leading up to and including ovulation. That is when pregnancy is most likely to occur. Experts believe the egg will survive for about 24 hours after ovulation unless it becomes fertilized.

How Home Tests Work

Home ovulation predictor kits detect luteinizing hormone (LH) in your urine. Rising hormone levels signal ovulation is likely to happen in most women.

“The tests are helpful in showing the signs that you’re about to ovulate,” said Dr. Caitlin Pandolfo, OB/GYN at Essentia Health. “However, the tests only suggest you’re going to ovulate. They don’t confirm ovulation happened.”

Kits usually come with several testing strips so you can check for an LH surge in your urine several days in a row. You will need to test daily until you see a surge for the most accurate results.

Some Benefit More Than Others From Ovulation Kits

While individuals with regular cycles can benefit from more closely tracking monthly patterns of their LH surge, over-the-counter ovulation predictor kits can be especially helpful for those with irregular cycles.

“If your cycle isn’t predictable, it’s hard to track your fertile window using an ovulation calculator, so tests are very useful,” Dr. Pandolfo said. “However, if your periods are irregular due to PCOS, ovulation tests are unlikely to help, because women with PCOS can already have high LH levels.”

It’s also important to keep in mind that women who are taking hormone replacement therapy to treat PCOS, hypogonadism (ovaries produce little to no sex hormones), or other conditions, may have reduced LH levels. 

Drawbacks to Testing

According to the U.S. Food and Drug Administration (FDA), home ovulation urine testing is around 90% accurate. However, certain types of tests may be easier for women to use and interpret.

“I recommend patients use the digital ovulation kits because it is easier to understand their results,” Dr. Pandolfo said. “Instead of trying to judge how pink a line is, you get a smiley face that doesn’t leave any room for misinterpretation.” 

Digital tests are usually more expensive, but Dr. Pandolfo says the cost can be worth it when trying to conceive. She also cautions against tests that use an app to decode the color of the test strip. Ovulation kits that test your saliva instead of your urine are also far less reliable.

Occasionally, ovulation tests can give false negative or false positive results, even for women without PCOS. It is important to carefully follow the kits’ directions. Make sure you do not drink too much water before testing, which can dilute your urine and skew your results.

Other Methods of Tracking Ovulation

There are other ways to increase your chances of identifying your fertile days every month, such as –

• Monitoring your cervical mucus and looking for a clear, stretchy consistency
• Tracking your basal body temperature, which will increase slightly after ovulation
• Using the calendar method or a period tracking app

If you choose to monitor your temperature, you should take your temperature with a digital thermometer first thing in the morning before you get out of bed.

“It can be hard for people to maintain compliance with basal body temperature readings, but tracking cervical mucus can be a consistent way for people to tell when ovulation is happening,” Dr. Pandolfo said. “I would be careful solely relying on predictive tracking apps without also monitoring temperature, mucus, or using test strips. Apps are not always effective or correctly predictive.”

Preconception Planning Can Help

If you’re thinking about having a baby, it’s a great idea to see your Essentia Health pregnancy provider before you start trying to conceive.

“Your provider can make sure you don’t have any medical conditions that could affect the safety of a pregnancy or your fertility,” Dr. Pandolfo said. “We can also verify that any medications you take are safe for pregnancy and switch you to other prescriptions if needed.”

During a preconception visit, you should talk with your provider about whether your cycle is regular. Your provider will review your medical history for conditions that could affect your fertility, including –

• Being age 35 and over
• Conditions such as hypertension, diabetes, or auto-immune disorders
• Endometriosis
• History of infertility or miscarriage
• Irregular periods
• Painful periods
• PCOS

“If you have any risk factors that may make it difficult for you to get pregnant, it’s good to know in advance,” Dr. Pandolfo said. “This way, we can shorten the timeline for any needed fertility interventions.”

Most women will not get pregnant in their first month of trying. There is only a 20% to 30% chance of getting pregnant in any given cycle. However, about 85% of women under 30 will get pregnant within 12 months of trying.

“If you’re not getting pregnant immediately, it’s not necessarily a reason for concern,” Dr. Pandolfo said. “However, if you have been trying for over a year, or if you are 35 or older and have been trying for at least six months without a positive pregnancy test, you should talk to your OB/GYN about fertility testing.”