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Getting Started with Chart Neo & Tempdrop

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This guide was originally created for the Tempdrop Group, a Facebook group for users who have purchased a Tempdrop (TD), which is why there is a heavy focus on Tempdrop integration in this guide. However, you do not have to own a Tempdrop to use the Chart Neo app.

The Chart Neo app is primarily designed to work with the Neo Fertility protocol. The Neo Fertility protocol combines aspects of Creighton, Billings, and Sensiplan protocols. The Chart Neo app will automatically sync with Tempdrop (a wearable charting thermometer) and it is available on both Apple iOS and Android.

There is a FREE initial trial for the first 45 days and then the app costs $9.99 USD/year. Note that the subscription is for a userid that can be used across platforms. No need to purchase multiple subscriptions for different devices. A single subscription will allow you (or your spouse, etc.) to login and access your chart on iOS, Android, and web.

Example of a Neo Fertility chart in the Chart Neo app

The Chart Neo app marks the BBT coverline and temp shift according to Sensiplan rules. The app encourages Creighton/Justisse style CM (cervical mucus) observations with the addition of Billings style CM sensation observations (aka “Walking Sensation”), which has been integrated into a system called WWIT observations. WWIT stands for Walking Sensation, Wiping Sensation, Inspect and Test. Learn more about WWIT observations from this Neo Fertility video:

Neo Fertility Chart Coding Key

source: “Neo Fertility, Advanced Fertility care through cycle tracking” by Phil Boyle (https://amzn.to/2r4kBdU)

How To Connect With Your Tempdrop Data

In the Chart Neo app go to Settings > Tempdrop > Link to Tempdrop
Be sure to have your Tempdrop account login handy.

explained with pictures

Go to Settings

Select Tempdrop

Select Link to Tempdrop
Be sure to have your Tempdrop account login handy.

How To Manually Pull Tempdrop Temps After Initial Setup

On the Daily Entry Screen (shown below) click the Temperature box. Note: Swipe left to go to the daily entry screen for previous days.

On the Temperature Entry Screen (shown below), click the Tempdrop symbol to tell the app to look for a Tempdrop temp for that day. Then just click the arrow in the top left corner to go back.

After the initial setup, you normally do not need to manually tell the app to look for Tempdrop temps for new temps. It will automatically look when you first go to the daily entry screen. If there was a previous temp that got updated by Tempdrop, then the app will show you a screen like this.

Self-Interpreting & Charting In Fahrenheit

As previously stated, the Chart Neo app marks the BBT coverline and temp shift according to Sensiplan rules. If you would like to self-interpret your BBT chart in the Chart Neo app, then please note that it can be a bit different than some manual charters may be used to. First thing to understand is that temps in the Chart Neo app are always graphed in rounded Celsius.

This is how it works:

  • Raw Temp from TD in C -> Rounded to 0.05ºC -> Converted to F -> F Temp Displayed
  • Raw Temp from TD in C -> Rounded to 0.05ºC -> C Temp Displayed

There are no rounded-in-F temps. Note: if you are using the Chart Neo app without Tempdrop, then always enter the raw F temp and not a rounded F temp.

The temp display can show Celsius numbers or Fahrenheit numbers, but it is the exact same rounded-in-C temp.

Does this mean as a Fahrenheit user, I should just switch to charting in C?

No, I recommended you continue to chart in your native temp scale. In Fahrenheit you use the number displayed as a range check, such as too high means possible fever and too low means too loose armband. This is most intuitively done in your native temp scale. So, the Fahrenheit number display is still useful even if you do not use the number to self-interpret your chart.

Ok, so how do you self-interpret without looking at the displayed numbers?

You do this by looking at the dot pattern or deviation pattern. The horizontal lines shown on the Chart Neo app chart are separated by 0.05ºC, which equals approximately 0.1ºF. This is 1 deviation or 1D. When you are looking for a temp to be 0.2ºC (approximately 0.4ºF) above the coverline, you are looking for a temp that is 4 deviations (4D) above the coverline. That means you count 4 lines above the coverline and look at that point or above to find it. This way of chart reading works for any chart displayed with a proper horizontal grid behind it, like most paper charts.

  • 1D = 0.05ºC (0.1ºF) -> count up 1 horizontal line
  • 4D = 0.2ºC (0.4ºF) -> count up 4 horizontal lines
How does this work in practice?

To read a BBT chart, you are first looking for the pattern of a temp that is at least 1D above the previous 6 temps. Remember, the coverline will be drawn Sensiplan-style, THROUGH the highest of previous lower 6 temps. Please note, if you use a charting method with a raised coverline, like TCOYF, then manually interpreting a chart displayed in the Chart Neo app may be more difficult, because you cannot change where the coverline is drawn.* However, if you use one of the many methods that marks the coverline through the highest of the pre-shift six temps, then self-interpreting a BBT chart from the Chart Neo app should be fairly straightforward once you learn to count the deviations. Next, after your first raised temp is recognized, to identify a full thermal shift pattern, you are looking for the second raised temp to again be at least 1D above the coverline (count 1 line up). Finally you want to see that third raised temp be at least 4D above the coverline (count 4 lines up).

In the Chart Neo app, you are able to self-read the BBT pattern and count where the graphed temp dots are in relation to one another. So, you are looking for things like at least a 4D change (counting up 4 lines from where the coverline is drawn). It is not necessary to subtract temp numbers to see if you get a change of 0.4F.

*More about the using TCOYF to read Chart Neo app BBT charts: If you still wish to evaluate your Chart Neo app BBT chart by TCOYF rules, then you will have to mentally add 1D (0.1ºF) to the TCOYF protocol, because the Sensiplan coverline is 1D lower than the TCOYF coverline. So, for example, when looking for a temp that is raised at least 0.3ºF above the coverline according to TCOYF rules, that turns into looking for a temp that is raised at least 0.4ºF (aka 4D) above the coverline in the Chart Neo app.

Sharing your Chart Neo app chart with Your Instructor

The Chart Neo app also has the functionality to allow your instructor to securely and privately review your chart. If you are interested in me reviewing your Chart Neo app chart, then feel free to contact me to get more info about how that works.