What is ovulation?

Ovulation is when you release an egg from one of your ovaries. From the five days before ovulation through to the day that you ovulate, you're potentially fertile. But your chances of getting pregnant are highest if you have sex in the last three days of this six-day window.  

When do you ovulate?

Generally, you ovulate in the middle of your menstrual cycle. If you have an average 28-day cycle, you may ovulate around day 14. However, lengths of normal cycles can vary from 21 to 35 days. Some women ovulate around the same day each cycle, but for others the timing is hard to pinpoint.

Learning how to identify and track ovulation symptoms can help you plan when to have sex if you want to get pregnant.

Ovulation symptoms

Almost all women have these three ovulation symptoms:

  • Changes in basal body temperature (BBT). Your BBT is your lowest body temperature in a 24-hour period. On the day after you ovulate, your BBT will go up by 0.5 to 1.0 degree Fahrenheit and stay elevated until your next period.
  • Changes in cervical mucus. Cervical mucus is the vaginal discharge you sometimes find in your underwear. During the few days before you ovulate and immediately after ovulation, you may notice an increase in cervical mucus and a change in its texture.
  • Changes to the cervix. During ovulation, your cervix is softer, higher, wetter, and more open.

The following symptoms are not as common or consistent as the ones described above, so you may have all, some, or none of them. They may include:

  • Breast tenderness
  • Mild cramps or twinges in the abdomen, or a one-sided backache, known as mittelschmerz (German for "middle pain")
  • Very mild spotting (vaginal bleeding or discharge that may occur when an egg is released)
  • Heightened sense of smell
  • Increased sex drive (some women say they feel sexy, flirty, more sociable, and more physically attractive)
  • Changes in appetite or mood
  • Fluid retention

graphic explaining 10 signs of ovulation

How to calculate ovulation

There's no foolproof method to predict when you'll ovulate. But here are a few ways you can estimate when it's most likely to happen, so you can try to time sex or intrauterine insemination (IUI) accordingly and boost your chances of getting pregnant.

(If that egg gets fertilized by a sperm and implants in your uterus, you're pregnant!)

Try the calendar method

If your cycle is regular – the same number of days each time – you can try the calendar method (also known as the Standard Days Method).

To estimate when you'll ovulate:

  1. Find your expected ovulation day: To do this, count back 14 days from when you expect your next period.
  2. Calculate your fertile window: This includes the day you ovulate and the preceding five days. So, for example, if day 1 is the first day of your period and day 28 is the day before you expect your next period, you'd be fertile on days 9 through 14.
  3. Emphasize the last three days: You're much more likely to get pregnant during the final three days of your fertile window than during the days immediately after you ovulate. This is because your egg survives in your fallopian tube for 24 hours after ovulation. And although sperm can survive in a woman's body for up to five days, they are more likely to fertilize your egg within three days of having sex.

This method is the easiest way to estimate your fertile window, but it's not very accurate, even if you have a good idea of when your next period will start. That's because ovulation rarely happens exactly 14 days before menstruation.

In one large study of women with 28-day cycles, the day of ovulation varied from seven to 19 days before menstruation. Ovulation happened 14 days before a period only 10 percent of the time.

So you can see how it's possible to miss your fertile window altogether using this method. On the other hand, it's simple, free, and worth a try, especially if you're not in a hurry to conceive.

Use an ovulation calculator

You can use BabyCenter's Ovulation Calculator to find out which days you're likely to be fertile according to the calendar method and what your due date will be if you conceive. It's one quick and easy way to figure out how to increase your chances of getting pregnant

Use an ovulation predictor kit

Testing your hormone levels with an ovulation predictor kit (OPK) is a more dependable way to identify your fertile window, though it doesn't work perfectly for all women.

There are two kinds of kits:

  • Urine tests: This is the most common. The pee-on-a-stick test indicates when your level of luteinizing hormone (LH) has gone up, which usually means one of your ovaries will soon release an egg. Some tests measure the level of another hormone, estrone-3-glucuronide (E3G), that also goes up around the time of ovulation.
  • Saliva tests: With the saliva test, you use a microscope to spot a pattern in your dried saliva that indicates the rise in estrogen that happens in the days before ovulation.

Both types of tests show a positive result in the days before you ovulate, giving you time to plan ahead for baby-making sex.

The kits are available at drugstores or online without a prescription. They can cost between $10 and $50 each.

Chart your cycle by monitoring ovulation symptoms

You can track subtle changes in your basal body temperature, cervical mucus, and cervical firmness for a few cycles to try to determine when you ovulate.

If you pay attention to these clues and note them on a chart or app, you may see a pattern that can help you predict when you're likely to ovulate next. (If your periods are irregular, however, you may not notice a pattern.)

Charting is free (after you buy the thermometer), but this method takes time and effort to do accurately.

Here's how you track each symptom:

  • Basal body temperature: You use a special basal thermometer (that you can buy online or at a drugstore) to measure your BBT every day, right when you wake up and after you've had at least three hours of uninterrupted sleep. After ovulation, your BBT will rise 0.5 to 1.0 degree Fahrenheit and stay that way until you get your period. The change in temperature doesn't tell you when you're going to ovulate, only that you have ovulated, so it's important to use this method in tandem with observing the changes in cervical mucus throughout your cycle.
  • Cervical mucus: For most of the month, you may have very little cervical mucus, or it may be thick and sticky. But in the few days before, during, and immediately after ovulation, you'll notice an increase in cervical mucus and a change in its texture: It will turn clear, slippery, and stretchy (like raw egg whites). This is the time, just before ovulation, when intercourse is most likely to lead to conception.
  • Cervix changes: As you approach ovulation, your cervix will become soft, high, open, and wet – you can remember this with the acronym SHOW. After ovulation, these signs reverse and the cervix becomes firm, low, closed, and dry. You can feel these changes if you reach inside your vagina with a finger. Read on for more in-depth information on checking your cervix.

It can also help to be aware of other ovulation symptoms you might have, such as spotting or cramping. Although this isn't a precise way to determine when you're ovulating, it may be helpful to be aware of these symptoms (if you have them) while using the calendar, OPK, or charting methods.

How to check your cervix for signs of ovulation

If your other fertility signs are obvious – you produce fertile-quality cervical mucus leading up to ovulation and have a sustained temperature shift following the buildup of cervical mucus that confirms ovulation – you shouldn't need to check your cervix. But if there's any ambiguity, your cervix offers good information to back up the other two signs.

Many women aren't familiar with touching their cervix. And when they do, they may not know exactly how it should feel. (How soft is "soft," for example?)

Here's what you need to know about checking your cervix:

  • Check when your mucus changes consistency: The best way to learn about your cervix is to start checking it once your cervical mucus changes consistency and to continue checking for a few days after your temperature has risen. That phase of about five days is when you'll notice the most abrupt change.
  • Insert finger to middle knuckle: To check your cervix, insert your clean middle finger into your vagina up to at least your middle knuckle or even farther. Notice how the cervix feels to the touch. Just before ovulation it may feel like your lips. After ovulation it will feel harder, like the tip of your nose.

Learn more about ovulation tracking

Find out more about how keeping track of your BBT and ovulation symptoms can help you predict ovulation. Then follow the steps to charting your BBT and cervical symptoms.