Unless you're currently trying to conceive, you probably haven't heard or thought about ovulation since high school biology or sex education class.

What Is Ovulation?
At its most distilled, ovulation is the phase during the menstrual cycle when a person can become pregnant. (ICYWW: The other three phases are menstruation, the follicular phase, and luteal phase). 

On a biological level, ovulation is the time during a person's menstrual cycle when an egg is released from one of their ovaries, where it is usually stored, explains Cristin Hackel, M.S.N., R.N., WHNP-BC, Medical Provider at Nurx. After leaving the ovary, the egg travels down through one of the fallopian tubes, which are two tunnel-like structures that connect the ovaries to the uterus, she explains. This journey typically takes the egg 30 hours, according to the University of California San Francisco Health. If there are any sperm present in the fallopian tube, where sperm can live for three to five days, one may fertilize the egg to create something called a zygote, she explains. "If that happens, the zygote will then move to the uterus to implant itself [at which point it becomes an embryo] and may begin to form a pregnancy," she says. 

If no sperm are present during the day-plus-long span that the egg is in the fallopian tubes, the egg cannot be fertilized, and therefore pregnancy is not possible, says Asima Ahmad, M.D., M.P.H., chief medical officer with Carrot Fertility. 

Similarly, if you have a regular cycle (which lasts from 21 to 35 days), there are no eggs in your fallopian tubes the weeks you aren't ovulating, which means that there is no egg available for the sperm to fertilize. That means that despite the misconception that pregnancy can happen every (!) single (!) day (!) during the menstrual cycle, it very rarely happens outside of the ovulation window for people with regular cycles. (But keep in mind: Because flukes happen, there are no "safe" days to have unprotected sex if you don't want to get pregnant, per the National Health Service). 

How Often Does Ovulation Occur — and How Long Does It Last?
Typically, ovulation occurs just once per month. During a regular 28-day menstrual cycle, ovulation usually takes place on the 14th day, according to the Cleveland Clinic. (As a refresher: The first day of the menstrual cycle is the first day of your period). 

However, "there are medical conditions that prevent people from ovulating every month," such as primary ovarian insufficiency (POI) or polycystic ovary syndrome (PCOS), says Dr. Ahmad. Many hormonal methods of birth control prevent unwanted pregnancy by preventing ovulation altogether, she adds. 

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While rare, there are also some people who ovulate more than one time per month, according to research published in The BMJ. When someone ovulates more than once per cycle, this is known as hyperovulation. Currently, not much is understood about the causes of hyperovulation. But taking fertility medication or having twins run in the family may increase an individual's likelihood of ovulating multiple times per month. 

While ovulation is usually about one day long, the ovulatory window is slightly longer. Ovulation refers to the specific day that the egg drops from your ovary. The ovulatory window, also known as the fertility window, is the multi-day span when pregnancy can take place. Typically, the ovulatory window is considered to be seven days long, according to Johns Hopkins Medicine.

The Benefits of Tracking Ovulation
Given that the ovulation window is the only time when someone can get pregnant, it should make sense that someone who is trying to get (or trying to avoid getting) pregnant would want to know when they are ovulating. "If you are trying to get pregnant, [the ovulatory window is] the days when you would want to have intercourse, while if you don't want to become pregnant those are the days when you would want to use a barrier (such as a condom) or abstain from intercourse," explains Hackel. 

It's especially important for people undergoing fertility treatments with the hopes of becoming pregnant to track ovulation, according to Dr. Ahmad. For example, someone undergoing intrauterine insemination (IUI), a procedure that involves medically placing sperm into the uterus using a small catheter, needs to know when they're ovulating, per the Johns Hopkins Medicine Center.

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Tracking ovulation, however, isn't just beneficial for people who want to be with child and those having the kind of sex that can result in pregnancy. The practice can tell you a lot about your overall health, according to an article published in the journal The Linacre Quarterly. 

For example, ovulation can be greatly affected by changes in hormone levels and illnesses, noted the researchers. As such, paying attention to your discharge during your ovulation window, how often you ovulate, and how you feel while you're ovulating can all give you insight into your overall health status, they note. Changes and abnormalities in ovulation may be able to help a clinician identify underlying sexually transmitted infections, reproductive abnormalities, hormone imbalances, and more, says Hackel. On the flip side, identifying ovulatory changes on your own can help you recognize when it's time to talk to a health-care provider to make sure everything is okay. 

Given that ovulation is just one phase of the overall menstrual cycle, these findings align with the American College of Obstetricians and Gynecologists (ACOG)'s decision to name the menstrual cycle the fifth vital sign (alongside body temperature, pulse rate, respiration rate, and blood pressure). "By including an evaluation of the menstrual cycle as an additional vital sign, clinicians reinforce its importance in assessing overall health status for patients and caretakers," wrote the ACOG team in a statement about the decision. 

Tracking ovulation may also help you get the most out of your workout routine. People who can get pregnant typically experience a noticeable burst of energy when they're ovulating, according to the Office on Women's Health. As such, it's typically the best time of the month to do high(er) intensity workouts, Alisa Vitti, functional nutrition and women's hormone expert and founder of FLO Living and the MyFLO app, previously told Shape. Someone really invested in PR-ing a race or reaching the podium at a CrossFit comp, for example, might intentionally choose to sign up for an event when their ovulation prediction app predicts they'll be in their ovulation window.

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How To Track Ovulation
Now that you're up to speed on the benefits of knowing when you're ovulating, you probably want to know how to track ovulation. Ahead, Hackle outlines four ways to track when you're ovulating.  

Chart your basal body temperature. 
"Your body temperature rises when you are ovulating," explains Hackel. Most people's temperature is 96° to 98° F before ovulation and goes up about four-tenths of one degree during ovulation to 97°–99°F, according to Planned Parenthood. 

When you take your body temperature when you're totally at rest, that's known as taking your basal body temperature. Taking your basal body temperature every single day before you get out of bed for the day — and logging it in an app or fertility awareness method chart — will allow you to observe body temperature changes and therefore predict and observe your ovulation window, says Hackel. Since the changes in temperature are so small, you'll need a special basal temperature tracker to do this correctly.

Try the cervical mucus method.
Your snail trail may give you some insight into whether or not you're ovulating. "There are changes in the cervical mucus (vaginal discharge) released by the vagina that can be evaluated to see if it seems that ovulation has occurred," says Hackel. 

While everybody is different, typically the cervical mucus is white, thicker, and sticky before ovulation and changes to be more clear, wet, slippery and stretchy like an egg yolk right before and during ovulation, she says. That's because the hormones that control your menstrual cycle also cause the cervix to produce a special kind of mucus, which gets released through the vaginal canal, according to Planned Parenthood.

What Does the Color of Your Discharge Really Mean?
There are a variety of ways to check this mucus. One is to wipe your vagina ahead of using the toilet for the day when you wake up, then touching the discharge on the TP to get a sense of its color and feel. Another way is to simply eye the discharge in your underwear. But the most accurate way is to put a clean finger inside your vaginal canal and swipe around, then remove your finger and rub the consistency between your fingers (of course, wash your hands immediately afterward).

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After checking the mucus, log the findings in a printable chart or app. After a few months of daily tracking you'll have a better understanding of what kind of discharge you produce at different points in your cycle, and therefore can make a point to avoid (or prioritize) unprotected intercourse in and around your ovulation window, says Hackel. 

"Using the basal body temperature method with the cervical mucus method is the best way to get an accurate idea if ovulation is occurring," says Hackel. When used together, it's known as the symptothermal method. 

Use an ovulation tracker app.
You can also try using an ovulation tracking app, which, FTR, is different from a basic period tracking app. "Period tracking apps let you know when to expect to bleed, which is helpful to know when you may need to have sanitary products on hand," explains Hackel. On the other hand, "ovulation tracking apps typically try to predict when the bleeding will occur, but they look at other bodily changes as well," she explains. Generally, these apps require more input from you, asking you to log body temperature, cervical mucus findings, cervical position (aka how high or low your cervix is positioned in your vagina), and other symptoms in order to better predict your ovulation window. 

The main benefit of ovulation tracking apps is that they let you keep track of basal body temperature and cervical mucus right from your phone, rather than requiring a pen and paper. Plus, there is less risk of forgetting to log your symptoms as most send daily reminders. 

Worth noting: Some period and ovulation tracker apps do double duty, predicting when you're going to be ovulating based on the duration of your average period. But unless the app also gathers information about the aforementioned ovulation symptoms, it's going to be less accurate. 

Rely on an at-home ovulation test.
If you're simply looking to know whether or not you're ovulating on one given day, at-home ovulation tests such as Modern Fertility Ovulation Test or Natalist Ovulation Test Kit are decent options. 

"Ovulation test kits are over-the-counter tests that detect how much luteinizing hormone (LH) is in your urine," and thus function much like at-home pregnancy tests, explains Hackel. "LH signals to the ovaries when it's time to release an egg, so the amount of LH present in the pee increases about 36 hours before ovulation," she says. 

They can cost about $.80 per test, and it's not particularly efficient to pee on one of these every single day. But when combined with any of the other aforementioned methods, they can be useful. 

The Takeaway on Ovulation Tracking
Tuning into when you're ovulating and various symptoms associated with your ovulation window can give you a lot of data about your body and the likelihood of getting pregnant. But beyond that, tracking ovulation can give you information about your overall health and well-being, too.