BBT (Basal Body Temperature) Chart – Everything You Need To Know

Basal Body Temperature Chart

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Do you wish to start a family and your doctor has asked you to keep a track of your BBT? Are you confused about what all aspects you should take into consideration while tracking your BBT and how to chart the information? Well, if you can relate to any of the above situations reading this post is a good idea.

If you have to maintain a BBT chart for any reason, read on to understand all about BBT and how you can track it.

What Is Basal Body Temperature (BBT)?

BBT, or basal body temperature, is your body’s lowest temperature in a 24-hour period. It is usually your body temperature during sleep or rest time. [1] You should measure your basal body temperature immediately after you wake up and before you take part in any physical activity. Even when you do so, the temperature reading that you get will be slightly higher than your normal basal body temperature.

If you want to learn how to measure basal body temperature, you will need a basal thermometer instead of a regular thermometer. A basal body temperature thermometer is very sensitive and can measure even the minutest changes that may take place in your body’s temperature. To accurately track the changes in your basal temperature over a period, it is important that you wake up and take your basal body temperature at the same time each day.

[ Read: Right Age To Get Pregnant ]

How To Understand The Variations In Your BBT?

Your BBT will most likely be in the range of about 97.2 degrees F to about 97.7 degrees F before you start to ovulate. Once you begin to ovulate, your body will go through various hormonal changes. The changes can result in a slight increase of about 0.4 to 1.0 degree F in your basal body temperature. The change in temperature will last at least till the time you start your next menstruation cycle.

It is possible that occasionally, you notice a rise in your temperature. If your rising temperature stabilizes and you notice the change over three days, it means you have started ovulating.

There are certain conditions during which your basal body temperature may not read correctly. If you are not well, or if you forgot to take your temperature immediately after waking up, the reading will most likely be inaccurate.

[ Read: Tips To Improve Your Chances Of Getting Pregnant ]

The following factors too can cause changes in your BBT:

  • Illness or fever
  • Anxiety and stress
  • Work in shifts
  • Irregular sleep or oversleeping
  • Alcohol consumption
  • Travel to different time zones
  • Gynecological problems
  • Medications [2]

Also, note you may ovulate without experiencing a clear rise in your basal temperature.

[ Read: How Long Does It Take To Get Pregnant ]

How To Track Your Ovulation Cycle With A BBT Chart?

A BBT chart can only tell you that you have already started ovulating. Tracking the changes in BBT in the first month may not prove to be very helpful at first glance. Once you start making a monthly basal body temperature chart, you will be able to notice a pattern that will help you to predict the next time you are due to ovulate. If your purpose of charting your BBT is to plan your pregnancy, it will help you identify the days you are most fertile and likely to conceive.

The day that your basal body temperature is at its highest is the day you will be most fertile. The few days leading up to this particular day will also be some of your most fertile days.

[ Read: How To Know When You Are Ovulating ]

Tips To Chart Your BBT

Here is a step by step guide on how to chart BBT:

  • Take your temperature the moment you wake up in the morning. Make sure you do so even before you sit up or talk to your partner. The idea is to take your temperature before you do even the minimum activity.
  • To make sure you do not have to look for your basal thermometer in the morning, always keep it handy. You can keep it on a bedside table so that you can easily use it first thing in the morning. If you are using a glass thermometer, shake it well at night before going to sleep, so that you do not have to do it in the morning.
  • Set an alarm for each day so that you can wake up around the same time to take your temperature. It will help you track your basal body temperature accurately. Avoid a time difference of more than half an hour. For example, if you took your temperature at 6 am today morning, it is okay if you take it at 6:30 am the next morning. However, if you consider taking your temperature at 6 am one day, and 7 am the next, the readings will not be conclusive.
  • To understand your temperature variations, remember that the normal variation is up to 0.2 degree F per hour. It will be lower if you take your temperature early, and higher if you take it later.
  • You should have a minimum of five hours of sleep before you take your basal body temperature.
  • You can take your basal body temperature in three different ways – orally, through your rectum or your vagina. Keep in mind that whatever method you adopt the first time you should continue to follow the same.
  • Also, to get the most accurate reading, you should make sure that you place your basal thermometer exactly the same way as you do it the first day. For example, if you are taking your temperature through your rectum or vagina, you should ensure you make the thermometer go as deep as you did on the first day. If you are taking your temperature orally, make sure you place the thermometer in the same part of your mouth as you did the first time.
  • Note your temperature on the chart every single day.

Once you have charted your BBT for a couple of months, you can speak to your doctor about it and share the same.

Did you chart your BBT? Do share your tips and advice for making and using a BBT chart with other women here.

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