Ovulation occurs when a person’s ovaries release an adult ovum. This usually occurs about halfway through the menstrual cycle, on or about day 14. After ovulation, the ovum moves from the ovaries to the fallopian tubes, where it can be fertilized if sperm is present. If an egg is fertilized and implanted in the uterus, a pregnancy results.
Knowing when you are ovulating can help you get pregnant or avoid pregnancy. You will probably get pregnant if you have unprotected sex up to three days before, or within a day after you ovulate. This is because sperm can survive in the reproductive tract for days, but once an egg is released, there is only a small amount of time it can be fertilized in the fallopian tubes.
Learn more about ovulation and its role in pregnancy, below.
Ovulation occurs when an ovum is released from the ovaries. The cycle begins on the first day of your period and lasts until the day before your next period. A menstrual cycle lasts an average of 28 days, although it can be longer or shorter.
Ovulation occurs approximately in the middle of the cycle, or 14 to 16 days before the start of your period. Although most people with a uterus have two ovaries, in most circumstances only one egg is released each month.
A person’s cycle includes two phases.
The follicular phase is the first half of the cycle when your body produces both follicle-stimulating hormone (FSH) and luteinizing hormone (LH).
- FSH causes the growth of a number of ovarian follicles, each containing one egg. At one point, one follicle develops faster than the rest. This is the egg that will be released during ovulation.
- At that point, estrogen levels cause FSH levels to drop, so one follicle continues to develop.
- A surge in LH in the days before ovulation helps that egg mature, preparing it for possible fertilization.
The luteal phase is the second half of the cycle when the actual release of an egg from the ovaries occurs. This is typically 10 to 12 hours after LP peaks.
- At that point, the egg is picked up by the fimbriae tubae – the finger-like protrusions of the fallopian tube – and begins its journey through the reproductive tract.
- If the egg is fertilized in the tube, it will move to the uterus and implant, resulting in pregnancy; if not fertilized, it will disintegrate as it moves through the uterus. If the pregnancy does not implant in the uterus, it can lead to an ectopic pregnancy.
Signs of ovulation
Some people experience subtle signs of ovulation, such as bloating, pain on one side of the abdomen or spots. Other ways to detect ovulation traces include:
- Changes in cervical mucus
- Basal body temperature
- Ovulation tests at home
Changes in cervical mucus
The cervix naturally produces mucus, which changes color and consistency throughout the menstrual cycle. In the days before ovulation, your cervical mucus may increase in volume and assume an egg white consistency.
Many people have a feeling of wetness during those days. After you ovulate, your cervical mucus will become sticky and cloudy, and there will be much less of it.
Basal body temperature
Another way to predict ovulation is by tracking your basal body temperature.
Most people experience a small increase in their body temperature around ovulation. The change is very small – between 0.4 and 0.8 of a degree Fahrenheit. As a result, to predict ovulation using temperature, you need to buy a special basal body thermometer (which will measure temperature to two decimal places) and measure your temperature at the same time every day, usually before getting out of bed.
Follow signs of ovulation
Many applications are available to help people detect their basal body temperatures, cervical mucus and other symptoms to predict ovulation. These include:
Ovulation tests at home
Many people use home ovulation tests, which follow the LH surge so you can know what your most fertile days are.
According to one study, those who use home tests effectively target community on the fertile window, and there is a greater likelihood of pregnancy with successful timing. Sex on the day before the LH surge – which is only identifiable by home tests that measure estrogen – significantly increases the likelihood of pregnancy.
Knowing when you are ovulating can help you get pregnant or avoid:
- If you are trying to get pregnant: The chances of pregnancy are highest if you have sex two to three days before you ovulate or on the day of ovulation.
- If you are trying not to get pregnant: Using birth control is your best way to prevent pregnancy. Sperm can live up to five days in the reproductive tract, so you will want to avoid unprotected sex for at least five days before ovulation and two days after.
When ovulation does not occur
Most people who experience a regular menstrual cycle ovulate. However, there are some times when you will not ovulate, including:
Does birth control prevent ovulation?
Most forms of hormonal birth control – including the pill and hormonal IUDs – stop ovulation. Your cycle will return when you stop these forms of birth control. The time it takes to ovulate again will depend on the type of birth control you used.
Some people – including those with PCOS – do not ovulate regularly. It can cause or contribute to infertility.
With assisted reproduction, medication can be used to stimulate the development of multiple eggs, which can be released during ovulation. Other medications that stimulate LH are then used to “trigger” ovulation to occur – these are known as trigger shots.
Insemination or sexual intercourse can be determined with ovulation to increase the chances of pregnancy.
Getting pregnant without ovulation
During in vitro fertilization, eggs are removed directly from the ovarian follicles. For people who do not ovulate even with help, it can make pregnancy possible.
A word from Verywell
Understanding ovulation is an important part of taking care of your health. Knowing when you are ovulating can help you get pregnant faster or avoid unwanted pregnancies.
For most people, ovulation occurs around day 14 of their menstrual cycle. However, this may vary from person to person. Tracking signs in your body, such as a greater amount of clear cervical mucus or a change in basal body temperature, can give you more accurate information about when you ovulate.
While there may be a learning curve to track and understand your menstrual cycle as you ovulate, applications make it easier than ever to take control of your fertility. You can also try using a home ovulation test to increase your chances of accurately tracking ovulation.