When trying to get pregnant, many women use an ovulation chart to record basal body temperature (BBT) and help determine the most fertile days of their cycle. Immediately before ovulation, BBT drops slightly and then after ovulation, it rises a bit due to climbing progesterone levels. Using a special thermometer, called a basal thermometer, even very small changes in temperature can be measured and charted. Some basal thermometers can measure temperature in 0.1 degree Fahrenheit, or even 0.01 degree. This can allow you to monitor and chart ovulation times during your cycle.

A helpful tip for monitoring your basal body temperature (BBT) is to do it at the same time every day. I recommend starting it on day one of your cycle. This is when your period starts. Keep your basal thermometer on your nightstand or bedside table, as you will need to take your reading immediately upon waking – before going to the bathroom or moving about. If you can use a paper chart to mark your temperature, this will be a lot easier than having to boot up the computer first thing in the morning to enter a few digits.

Now, here come the rules of the game You have some options to choose from, you can take your BBT vaginally or orally, this does not matter as long as you take it in the same spot every time. As stated earlier you must take this after a prolonged period of rest, so no eating, drinking, or exercising before you take your temp. You must leave the thermometer in place as long as the instructions that came with your thermometer state. Most basal thermometers come with a chart in the box however, if you would rather print your own there are several websites that allow you to download and print out a blank ovulation chart. The Mayo clinic recommends using a graph to better visualize these changes every month.

Here’s how to tell when you have ovulated: the American Society for Reproductive Medicine have announced that when your BBT jumps about 0.5 degrees F, this indicates that your ovaries have already released an egg. This information is helpful because it helps you to anticipate when you’re going to ovulate the next month, and when you’ve got a few months of ovulation charts, predicting your ovulation date becomes easier and more accurate!

Unfortunately, these tips don’t work for everyone, so it’s important to work around your situation. For example, if you work irregular hours, such as shifts, you’ll need to take the readings at the same time of day (it could mean taking your temperature to work with you and setting an alarm). Similarly, if you’re stressed, suffering from sleep deprivation, experiencing jet lag or some other sleep disturbance, your readings may become erratic. Even lifestyle factors such as being a smoker or sleeping with an electric blanket can affect your reading.

Don’t be overly concerned if any of these factors are affecting you right now, just take the appropriate steps to overcome them. It could mean listening to a relaxation tape before going to sleep, in order to decrease stress and insomnia, or stopping smoking or the use of electric blankets. Even if your readings for one month are a little erratic, you need to persevere, as each additional month of accurate readings from your ovulation chart will bring you closer to your goal of getting pregnant.