October 2022

What is the basal body temperature method and how can it be used to track ovulation?

The basal body temperature method is a way to track ovulation and determine when you ovulate. People use this to aid in conception, by determining what days of the month you ovulate. This method can also be used for natural family planning to avoid pregnancy. Tracking your basal body temperature is an easy way to track your ovulation and no apps or extra tests are required.


What is basal body temperature?

You can track your basal body temperature with a thermometer that measures temperature to at least one-tenth of a degree. You can buy thermometers that are called basal body thermometers, but any thermometer that measures to one-tenth of a degree will work. To measure your temperature you must take your temperature at the same time every day. Your basal body temperature is the temperature of your body when at rest. In the morning when you wake up, is usually the best time to measure your temperature. You must measure your temperature from the same place every day also, this can be from the mouth. Writing the temperature down every day is important. As you begin tracking your temperature you will notice a rise in temperature. This slight rise in temperature occurs during ovulation. This increase is small, usually less than 0.3 degrees Celsius. After tracking your basal body temperature for a few months you can determine when you will ovulate and for how long. [1]




How can you prepare for tracking your basal body temperature?

This method doesn’t require extra preparation, just some patience and getting used to a new routine. You should speak with your doctor if you want to try this method and you have recently given birth, stopped taking birth control pills, are breastfeeding, or approaching menopause. All of these factors could impact your basal body temperature. Your basal body temperature can be influenced by other life factors. Such factors include:

  • Fever or illness
  • Feeling stressed
  • An interrupted sleep cycle
  • Alcohol
  • Time zone differences from travel
  • Gynecological disorders
  • Some medications


You should speak with your doctor about your lifestyle to determine if the basal body temperature method is right for you. Some women who work at night or have odd sleeping schedules may not be able to use the basal body temperature method as accurately. Your doctor will give you the best advice on if this method will benefit you. [2]


When are you most likely to get pregnant using basal body temperature?

Ovulation typically occurs about two weeks before your menstrual period. You are most likely to get pregnant two to three days leading up to ovulation and 12 to 24 hours after ovulation. Ovulation is when you are the most fertile and likely to conceive. Male sperm can live in the female reproductive tract for three to five days. When using the basal body temperature method there are some temperature ranges that you should look for to determine when you will ovulate. A typical basal body temperature prior to ovulation is between 36.1 and 36.6 degrees Celsius. During ovulation, your basal body temperature will rise by about 0.3 degrees celsius from your normal temperature. The temperature will remain higher until the end of your menstrual cycle. It will take a couple of months of tracking to determine your normal temperature and to predict when your temperature will rise. This method is an easy way to gain more information about your cycle and predict ovulation. [3]



1 https://my.clevelandclinic.org/health/treatments/21065-basal-body-temperature

2 https://www.mayoclinic.org/tests-procedures/basal-body-temperature/about/pac-20393026

3 https://www.medicalnewstoday.com/articles/basal-body-temperature#predicting-ovulation