7 Ways To Analyse Your BBT Chart For Fertility

Do you take your BBT temperature, but have no idea what your chart means? Maybe you’re just looking at when you ovulate, but don’t pay attention to the other details?

Charting is not just about when you ovulate. When you analyse your chart, then it will help you to work out what is missing, where your hormones are out of balance and what tests you need to get.

Find out the 7 most important things to analyse on your BBT chart in this week’s workshop with real examples to help you understand the practical implications and improve your fertility.

1. Total Length Of Cycle

The ideal length of a cycle is between 26 and 30 days. To show that your hormones are balanced, you also want it to be a fixed cycle, which means that it is always the same number of days. For more details look at the factors that make up a Conceivable Cycle.

2. Ovulation

To determine ovulation your temperature should rise by 0.2oC from your follicular phase to your luteal phase. When you’re assessing whether you have ovulated or not, then use different indicators in combination with your temperature to build your confidence of when it happens.

Note down your cervical fluid and cervix position around the middle of your cycle and use ovulation predictor kits.

Watch the video above for an example of figuring out ovulation timing when there are contradictory factors.

3. Follicular Phase Length

The follicular phase is the first part of your cycle from the first day of your period until ovulation. It is the part of your cycle that varies the most in length. Research studies looking at 20,000 cycles, showed that follicular phases vary from 12-20 days. In a Conceivable Cycle we are aiming to get a 14-day cycle, however, you can still get pregnant and have a healthy baby if you have a different length follicular phase. It’s important that the follicular phase is long enough for an egg to mature.

4. Luteal Phase Length

The luteal phase is the second part of your cycle, after ovulation and before your period. The luteal phase needs to stay high for at least 10 days (preferably 12-14 days) for the egg to implant and pregnancy to occur. Unlike the follicular phase, the luteal phase doesn’t vary very much.

Research studies across 20,000 cycles showed that 75% of them varied by only 4 days, with a length of between 10 to 14 days. The research showed that a normal luteal phase is 10-16 days. The outlier is 19 days and if you get a 20-day luteal cycle, then it’s highly likely that you’re pregnant.

The video above has an interesting example of an unusually long luteal phase and discussion around pregnancy.

5. Anomalies

Another key element of your cycle is to look for the odd one out. If there is a spike or dip in your chart that doesn’t fit with the rest of your readings, then figure out if there is an environmental reason why this has happened. Note down things like changes in sleep patterns, disturbed sleep, the time you take your temperature, if you drink alcohol or if you have a cold. All of these factors can throw your temperature off. When you find a spike or dip that is due to environmental reasons, then discount it.

6. Shape

As I’ve said before, it’s hard to make conclusions when you’re just looking at one chart. Wait until you have three charts and then look for the common themes between your charts. This is where the gold is and will help you to see the missing pieces and the reason why you’re not getting pregnant.

The patterns will show you where your hormones are not working properly and can then signpost what further tests to have. Look at your charts and find the patterns that are similar. If there is always a dip in temperature around implantation time, then you could start exploring reproductive immunology. Or maybe your temperatures rise too slowly after ovulation? This could mean that there is an issue with progesterone.

7. Temperature Ranges

Don’t get hung up on having to have the exact temperatures within the ranges outlined below. The shape and length are more important than the actual temperatures. If your pattern is following a biphasic curve, you’re ovulating and your cycle is nice and regular, then these factors are more important.

That said in a Conceivable Cycle we are aiming for follicular phase temperatures around 36.2-36.5oC or 97.2-97.7oF. And luteal phase temperatures around 36.6-37.0oC or 97.9-98.6oF.

Want more help figuring out your BBT chart for fertility? Join the Fertility Heroes private Facebook Group.

All my best,

Rachel xx

Rachel Bolton BSc (Hons), Lic. Ac., Lic. Tui Na.

I empower women to see themselves as Fertility Heroes and help them to optimise their fertility, get pregnant and have healthy babies.  

Whenever you're ready...here are 3 ways I can help you.

1. Join the private Facebook group: Fertility Heroes. Get fertility tips, community and inspiration. Only the women in the group will know you've joined and see your posts.

2. Take the Quiz: Which Fertility Hero Are You? Discover your superpowers, kryptonite and get your 3-point fertility formula.

3. Complete the Checklist: Why Am I Not Pregnant Yet? Find out what is missing from your fertility and get a new strategy.

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