UNDERSTANDING BBT - BASAL BODY TEMPERATURE

December 14, 2021

When trying to conceive, it’s important that you have sex before you ovulate. Sperm can live in the body for up to 5 days while an egg can only be fertilized for 12-24 hours after being released from the ovary (a process called ovulation). Ideally you want to have sperm waiting for the egg. Most ovulation signs appear a few days before your egg is released with 2-4 days prior to ovulation being your most fertile time.

Some signs of ovulation are SHOW:

Soft: The cervix will be soft and feels a lot like the tip of your nose

High: The cervix will be positioned higher up in the vagina

Open: The os (the small opening in the cervix) will open slightly to allow for the       

            sperm to enter

Wet: Cervical discharge will be clear and stretchy

These signs in addition to a slightly higher body temperature are all indicators that ovulation has occurred. Monitoring your daily basal body temperature (BBT) using a thermometer is one tool that you can use to monitor your ovulation which can increase your chance of conceiving. 

How to Take Your Basal Body Temperature 

With ovulation, a rise in body temperature takes place, caused by an increase of the hormone progesterone, in order to provide a warmer, more fertile environment. A minimum temperature rise of 0.4 to 0.6 degrees can be measured. By monitoring when this temperature change takes place, you can determine when ovulation takes place in your cycle. 

Take your BBT temperature first thing each morning at the same time every day. As any physical activity can increase your resting temperature, it is recommended that you take your BBT reading before you get out of bed. Follow product directions, read the temperature to within 1/10 of a degree, and record the reading on your BBT chart or app on your phone.

Predict Ovulation with BBT Charting

Start on day one of your menstrual cycle and record your BBT temperature on your fertility calendar or fertility chart. Each morning record your temperature at the same time prior to any activity including eating or drinking. Your temperature rise may be sudden, gradual, or in steps. The pattern may vary from cycle to cycle. For most women, 96-98 Fahrenheit or 35-37 Celsius degrees is considered a normal basal temperature preceding ovulation. Directly following ovulation, your BBT should rise about 2 degrees. By charting your temperature changes in one-tenth degree increments you can determine when ovulation has taken place. Typically a rise of at least 0.4 to 0.6 degrees will take place at ovulation, though for different women the temperature increases may be sudden or gradual. 

Basal Body Temperature - FAQ 

How do I take my BBT? 

Take your temperature first thing in the morning, prior to food, drink, or activity. Your temperature should be read lying in bed. A minimum of three to four hours of sleep is required before a BBT can be determined. Take your basal temperature even before moving around in bed. Read directions for using your BBT Thermometer. 

How does BBT charting "predict" ovulation? 

BBT charting helps you predict ovulation by determining fertility patterns in your cycle allowing you to predict ovulation based on your menstrual cycle/BBT history. But because temperature increases take place just following ovulation, BBT charting tells you when you have ovulated, helping you determine when your "window of opportunity" for conception will arrive. Many women use BBT charting and ovulation tests together to predict ovulation with increased accuracy. 

What should my BBT chart record?

The chart begins with the first day of the cycle (CD1) and monitors temperature increase on a daily basis in one-tenth of a degree increments. Check your BBT daily at the same time and record results on your BBT chart or phone app. 

What temperature changes indicate ovulation? 

Following ovulation, you can record a minimum body temperature rise of 0.4 to 0.6 degrees or more. Temperature baseline increase can vary among women. Temperature changes, depending on the individual, can be gradual or sudden. Once you can identify an increase in your basal body temperature you know that ovulation has taken place. 

Also note on your chart activities that give you a higher or lower reading including: Late night, drinking alcohol, time zones, breast feeding, illness, stress, drugs, and room temperature. 

Other things to note on your chart:

Sex, cervical mucus or CM, Cervical position, and desire for sex or arousal. 

Basal body temperature is just one way to monitor ovulation. It is inexpensive, but it does take a few months of charting to notice trends. Keep in mind that things like stress, illness, alcohol and disrupted sleep patterns can lead to inaccurate reads. It is also possible to ovulate without your temperature rising. Generally speaking, charting your BBT has about a 76-88% accuracy rate. If you are looking for something quicker and more reliable, ovulation predictors and strips are a better bet. 

If you ovulate and have a healthy menstrual cycle with bright red blood, you have a chance to conceive on any given month. No matter your choice, taking a deeper dive into learning about your body and how it operates throughout the month can be empowering and is worth considering.

Similar Blog Posts

Discover These 10 Steps to Improve Your Mindset Right Now

TAKE THE QUIZ

Contact Us

  • This field is for validation purposes and should be left unchanged.
Top crossmenu
0