Ovulation is a process in which the body releases an egg from an ovary in preparation for sperm to fertilize it. Ovulation lasts only around 1 day.

A photo of an egg in an egg carton to symbolize ovulation.Share on Pinterest
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It is part of the menstrual cycle, which most females experience from the onset of puberty until menopause.

In this article we discuss how long ovulation lasts, what happens during it, signs and symptoms, how to track ovulation, and when to see a doctor.

Ovulation only lasts around 1 day.

The body triggers the release of an egg from the ovaries. Once that egg starts its journey towards the uterus, it only stays viable for 1 day.

However, sperm can live in the uterus and fallopian tubes, the tubes that connect the ovaries to the uterus, for up to 6 days. This means that there are around 6 days of the menstrual cycle during which people can become pregnant.

The body produces the highest amounts of the hormone estrogen during ovulation.

This high surge of hormones causes the ovaries to release the egg into the fallopian tubes. The egg travels through them toward the uterus. Estrogen has already caused the uterus to thicken in preparation for implantation.

Once the ovaries release the egg, the levels of estrogen in the body begin to fall.

There are several signs and symptoms that a person is currently experiencing ovulation.

These include:

  • cervical fluid, also called vaginal discharge, that looks like raw egg white
  • slight decrease in basal body temperature, followed by a sharp increase after ovulation
  • the cervix will change position to being high, soft, and open

Some people may experience the following signs and symptoms:

  • light spotting
  • light cramping or pain on one side of the pelvis
  • breasts feeling tender
  • increased sex drive
  • a heightened sense of smell, taste, or vision

People can usually only get pregnant if they are having unprotected sex just before or during ovulation. People are most likely to get pregnant if they have sex within a day or two of ovulation.

However, it is possible for people to become pregnant if they have sex up to several days before ovulation because the sperm can swim up the fallopian tubes to wait for the ovaries to release the egg.

The best way to become pregnant is to have frequent unprotected sex before and during ovulation.

Some people may use signs and symptoms of ovulation as a way to avoid becoming pregnant.

Fertility awareness methods, which people may also know as natural family planning or the rhythm method, may help people plan their sexual activity around their ovulation so that there is less of a chance they will get pregnant.

However, a person who does not want to get pregnant should consider using birth control, which is much more effective at preventing pregnancy.

There are several ways in which people can track their ovulation to determine when they are at their most fertile:

  • the cervical mucus method, in which people check their vaginal discharge each day
  • the calendar method, in which people note their menstrual cycle on a calendar
  • ovulation predictor kits, which track LH hormone levels, as a surge in LH triggers ovulation. Note that these may be inaccurate in some people, including those with polycystic ovary syndrome (PCOS).

In contrast, for individuals who do not wish to conceive, various methods of birth control are much more effective.

According to Planned Parenthood, using condoms is 85% effective, using a birth control pill or patch is 91% effective, and using a birth control implant or hormonal intrauterine device (IUD) is 99% effective.

Hormonal birth control and certain health conditions can prevent ovulation.

There are several hormonal birth control methods that prevent the ovaries from releasing an egg.

These include:

Some health conditions that may prevent ovulation include:

There are four stages of the menstrual cycle:

  • the follicular phase
  • ovulation
  • the luteal phase
  • menses

The follicular phase

This phase typically occurs from days 0–14 of the menstrual cycle. If a person has a menstrual cycle that is not 28 days, it is because the follicular phase is either longer or shorter than 14 days.

During this phase, the hormone that the body produces the most is estrogen. This helps thicken the uterine lining, making it possible for a fertilized egg to implant itself there.

The higher amount of estrogen also makes it easier for sperm to enter the reproductive system. The estrogen changes the cervical mucus, making it easier for sperm to gain entry.

Ovulation

Ovulation occurs 14 days before the start of menses, the blood that comes out during a period.

If a person has a 28-day cycle, this means that ovulation occurs on day 14. People with a varied cycle will experience ovulation at different times.

Day 1 of the menstrual cycle is the first day of a period, or menses.

During ovulation, the amount of estrogen the body produces is at its highest. This surge in estrogen triggers a surge in LH, which then stimulates the ovary to release an egg. The cervix also produces more watery mucus to better accommodate sperm.

The luteal phase

In a 28-day cycle, this phase starts on day 14, and ends on day 28.

Instead of mainly producing estrogen, the body produces more of a different hormone, progesterone.

During the luteal phase, progesterone triggers the uterine lining to secrete substances that support a pregnancy.

The progesterone also decreases the amount of cervical mucus the body produces. The fertilization window has passed, so receiving sperm is no longer a priority for the body. The higher amount of progesterone also increases the body’s temperature.

If sperm fertilizes the egg, then the body maintains the higher levels of estrogen and progesterone as the egg implants itself into the uterine lining. However, if this does not happen, then the levels of estrogen and progesterone rapidly decrease as the body prepares for menses.

Menses

The drop in levels of estrogen and progesterone causes the uterine lining to shed. Menses typically happens on day 1 of the menstrual cycle.

Most menstrual blood is arterial, which means that the blood contains oxygen. Only 25% of the blood is venous, which means that it does not contain any oxygen. Venous blood tends to be darker in color than arterial blood.

The menstrual blood also contains tissue debris. A process called fibrinolysis prevents the menses from containing clotted blood unless a person experiences a heavy flow.

By tracking the menstrual cycle, people can learn whether their periods are regular or irregular and whether their symptoms are any cause for concern.

The easiest way to track the menstrual cycle is by marking when a period starts and ends on a calendar.

It may also be useful to track:

  • any premenstrual symptoms such as cramping and bloating
  • when bleeding begins
  • the heaviness of the bleeding
  • any period symptoms
  • when the bleeding ends

A person may consider tracking their menstrual cycle with an app. Several apps that track the menstrual cycle are available to download. Some are free and may be capable of tracking certain symptoms.

It is important to see a doctor if there are signs that something unusual is happening during the menstrual cycle.

Some signs that a person may need to make an appointment with a doctor are:

  • having had unprotected sex, then missed a period
  • having menstrual bleeding that is heavy enough that a person needs to change maxi pads or super tampons every hour
  • having a period that lasts longer than usual, or longer than 7 days
  • experiencing light-headedness, dizziness, or a fast pulse during a period
  • having clots or a gushing sensation
  • reaching 16 years of age and not having gotten their first period
  • having severe pain before or during a period
  • bleeding between periods
  • feeling sick or having a temperature when using a tampon
  • being unable to engage in everyday activities because of symptoms before or during their period
  • having a period more frequently than every 21 days or less frequently than every 45 days
  • experiencing feelings of anxiety or depression around the time of a period

These symptoms may be a sign that something unusual is happening in the body that is causing a change in the menstrual cycle.

Ovulation is a process where the ovaries release eggs in preparation for fertilization. It is a normal part of the menstrual cycle, which prepares the body for pregnancy.

The length of the menstrual cycle varies from person to person. Therefore, it is important for a person to keep track of what is normal for them.

A person should make an appointment with a doctor if they experience any concerning symptoms.