Are you looking for an inexpensive way of tracking your ovulation? Have you heard about basal thermometers, but not sure if they’re reliable?
Tracking your basal body temperature is one of the least expensive, yet reliable, ways of monitoring your cycle. Whether you’re looking to get pregnant or trying to avoid it, tracking your body temperature is a big part of natural family planning.
We’ve rounded up the best basal thermometers to help you find the right one for you.
- High precision
- Soft beep
- All-inclusive, good value package
- Impressive app functionality
- Data stored on the cloud
- 1-year warranty
- Comfortable to wear
- Reliable results
- Tracks temperature & sleep quality
- Smart technology
- Syncs automatically
- High precision
- Very accurate reading
- BBT chart included
- European CE and FDA-approved
What Is Basal Body Temperature (BBT)?
Basal body temperature (BBT) indicates the lowest body temperature within 24 hours (1). Now, you can’t just measure this at any given moment when you’re feeling colder. To get a correct reading, it has to be the first thing you do when you wake up.
As soon as you wake up and go to the bathroom, drink a glass of water, or perhaps enjoy a cuddle with your partner, your temperature rises. If you were to do just one of these activities before measuring your temp, it would be incorrect.
Before ovulation, your basal body temperature will be within the 97.0 to 97.7 F range. After ovulation, your BBT increases by a few tenths of a degree and will stay high until your next period. In other words, your cycle is divided into two parts: the first half is the cooler follicular phase, and the second half is the warmer luteal phase.
Separating the two is the temperature shift that marks that ovulation has occurred.
Before you ovulate, the high levels of estrogen in your body keep your BBT low. After ovulation, the body quickly begins to produce more progesterone. By looking for a sustained temperature rise for at least three days, we can confirm that you have ovulated and the body has moved onto the second phase of the cycle.
What Is a Basal Thermometer?
A basal thermometer looks and works very similarly to a conventional thermometer. However, they’re much more sensitive and can, therefore, measure smaller changes in your BBT (2).
For example, a conventional thermometer may give you a reading of 98.2 degrees Fahrenheit. The basal thermometer, on the other hand, would read 98.235 degrees Fahrenheit, giving you more decimal places and therefore a more accurate reading.
Can I Use My Conventional Thermometer?
Some argue that to get a correct reading of your BBT, all you need is a reading to the tenth degree. This is, of course, what you would get with pretty much any thermometer.
This might be enough for you if you’re not necessarily trying to conceive right away, or you’re just curious.
That said, if you want the best results, experts agree that you’ll need a thermometer that’s more sensitive. The temperature changes are small, and you might miss them with a less sensitive thermometer. If you have an irregular, short, or long period, it can be extra difficult to predict your ovulation and an accurate thermometer is a must (3).
Another reason to choose a basal thermometer is that many can store your readings. This way, you can wake up, take your temperature and then go back to sleep. Then later in the day, you can write it down, or sync it with an app.
How to Choose a Basal Thermometer
Basal thermometers come in all shapes and sizes. Some are high-tech and high-priced, while others look very normal.
Here are a few different types:
- Digital: These basal thermometers have a small display showing you the reading as well as an on/off button.
- Glass: Most doctors argue that glass mercury-free basal thermometers will give you the most accurate reading. These are fairly easy to use, and you won’t have to worry about battery life.
- Smart basal thermometers: These are the new competitors on the market. They often offer you a basal thermometer with a compatible app. These won’t look like a conventional thermometer, and they might be expensive.
When buying a basal thermometer, you should consider your needs, the accuracy, and your budget. These can be more expensive than regular thermometers, but if you’re trying to conceive, you’ll need that accuracy.
When shopping around, it seems that many women today tend to prefer digital models. However, if you’re thinking about buying a digital one, there are some things to consider beforehand:
This is a crucial feature. You’ll need one that will give you a reading to one-hundredth of a degree. If you buy one that will only give you a tenth, it won’t be sufficient for charting because it can not pick up very slight elevations in temperature.
Batteries or Rechargeable
Considering that you’ll be using the thermometer every day, so the batteries may not last long. Since there aren’t many on the market that are rechargeable, look for one that is energy efficient.
Digital basal thermometers seem to tend to stop working suddenly. Poor quality basal thermometers might fail after a month or so, but if it’s of good quality, this is less likely to happen.
This is a make or break point for me. Sometimes, life gets hectic and you won’t have time to write down your BBT. Unless you have a perfect memory, a memory feature is essential.
The Best Basal Thermometer Reviews of 2021
Here are 5 great basal thermometers for you to consider.
1. iProven Digital Basal Body Thermometer
For the best digital basal thermometer, we’ve chosen this cute little thermometer from iProven.
As I mentioned earlier, to get the best results, you need a sensitive thermometer. This one is ultra-sensitive, giving you a precise reading to one-hundredth of a degree. It’s not the fastest, but definitely not the slowest, providing results in about a minute.
When it’s finished its reading, it will make a beeping noise. But iProven states that it’s soft and shouldn’t wake any co-sleepers. This is one problem you often find with digital thermometers: the beep is too loud.
One thing that stood out to me was what iProven includes in the package. Besides the thermometer, you get a step-by-step guide as well as a temperature chart. I always prefer having a chart to write on as opposed to an app — it’s just easier for me.
The temperature chart will give you an overview of your cycle. This will help you identify your fertile window and assist your doctor in spotting any issues.
- Easy to use.
- High precision.
- Soft beep.
- Easy to read display.
- An all-inclusive, good value package.
- No backlight for this particular model.
2. Intelligent Basal Thermometer for Ovulation
This thermometer features a unique and ingenius mock lipstick design, allowing you to take your temperature without your family or co-workers knowing that you are trying to get pregnant.
The temperature is controlled via BlueTooth on your smartphone using the downloadable app (both iOS and Android). The application has impressive charting features such BBT Curve graph, automatic pregnancy rate calculation (based on the previous 7 days), and a daily record of all your key measurements. The data is also stored in the cloud, reducing the chance of all of your hard work being lost or destroyed.
The measurements are fast and accurate and can be taken in an average time of 90 seconds. To make matters simple and reduce the possibility of human error, there are no buttons or need to control the device. Once the lid is removed, it will automatically start recording and stop once the data transmission is complete.
- High accuracy.
- Easy to use.
- Impressive app functionality.
- Data stored on the cloud.
- 1-year warranty.
- The app was recently switched to a monthly fee subscription.
- Takes 90 seconds to read the temperature.
3. Smart Fertility Tracker from iFertracker
Wearing a basal thermometer might seem odd. But with this high-tech, sleek-looking model from iFertracker, you won’t notice.
Before you go to bed, place the sensor under your armpit. From here, it will record your temperature throughout the night.
One feature that I’m sure you’ll love is its thorough readings. During the night it gathers 20,000 temperature data points that you can look at through the app in the morning.
After pairing the sensor with the app, it will send all of the data automatically to your phone. However, since we sometimes tend to forget things, the sensor has a flash memory of 240 hours.
An additional feature that we can’t leave out is the sleep analyzer. The sensor will not only track your temperature but also how you sleep. How cool is that?
That said, the battery life of the sensor needs some improvement. If you wear it every day, like you’re supposed to, it will indicate “low battery” within a month.
The app also still requires some work, although it has already made vast improvements.
- Comfortable to wear.
- Reliable results.
- Tracks temperature and sleep quality.
- Short battery life.
- Connecting with your device can be difficult.
4. Easy@Home Smart Basal Thermometer
This smart basal thermometer from Easy@Home is well worth your time. The thermometer itself features a small, backlit screen displaying your results, which then sync to an app on your phone.
The basal thermometer has a high precision — it will measure down to the hundredth degree. Additionally, it will let you choose between Fahrenheit and Celsius.
This smart thermometer comes with the Premom app, compatible with both iOS and Android. When you create your account, it will give you unlimited cloud storage for all your recordings.
As you take your temperature in the morning, the results will seamlessly sync with your app. Even still, remember to connect the thermometer to your phone before you take your temperature. Otherwise, the results won’t sync automatically.
Once inside the Premom app, your data will be analyzed to give you an accurate fertility window. Following a month or so where it gets used to your regular cycles, the app will predict and even give you a warning before you ovulate.
However, the battery seems to run out rather quickly. For everyday use, it’s not very convenient.
- Smart technology.
- Easy to use — syncs automatically.
- High precision.
- Great app.
- Reasonably priced.
- Short battery life.
5. Generation Guard Basal Thermometer
This basal thermometer from Generation Guard is both European CE and FDA-approved.
Generation Guard specially made this basal thermometer for women who are trying to conceive. With its memory recall feature, it will be easier to keep track of your previous reading. To do this, switch off the thermometer, while off, long-press the button which will initially display the prior basal temperature reading. Release the button and it will auto-calibrate and the reading will then be flashed.
You can use this thermometer orally. Nevertheless, the tip is easy to clean and disinfect after use.
Alongside the thermometer, Generation Guard also provides you with a temperature chart. Here you can easily keep track of your cycles.
- High precision.
- Easy to find battery replacement.
- Basal body temperature chart included.
- European CE and FDA-approved.
- Only supports Fahrenheit reading.
Why Track Your Basal Temperature?
Ovulation occurs when the ovary releases an egg. The site of rupture left behind on the ovary is called the corpus luteum, and it starts producing progesterone, which is responsible for the increase in temperature.
Once you see a sustained rise in body temperature, it’s highly likely the egg has been released and has already died. You then move into the luteal phase, and can’t fall pregnant for the rest of the cycle. Ultimately, conception will occur when intercourse happens in the few days before ovulation.
If you’re using this method as contraception, keep in mind that semen can live inside a woman’s body for up to five days (4). Combine this with the fact that the released egg can live for 24 – 48 hours, and you have a roughly 6-day fertile window before and including ovulation day in which you could fall pregnant.
If you’re using this method to conceive, thermometers can confirm that ovulation has already taken place in a cycle, but only after the fact. Once you see a temperature rise, your chances of conception are very low, since there is no egg.
How to Track Ovulation Using a Basal Thermometer
To successfully track your cycle, the best thing to do is print out an ovulation chart or download an app. Some basal thermometers come with a compatible app that will help you out.
Then here’s what you do (5):
- Pick a time: The first thing you’ll need to do is choose a time to measure your temperature. It must be in the morning when you first wake up as well as at the same time every day.
- Note your period: The best time to start is when your period begins. Note this as day 1 and record your temperature.
- Continue through your cycle: Keep going and note when your period starts and stops. Every day, at the same time, take your temperature.
- Note your ovulation: After a couple of months, you’ll likely see a pattern. As we established above, before ovulation your BBT is lower — generally between 97.0 and 97.7 degrees Fahrenheit. When you increase to a range of 97.7 to 98.3 Fahrenheit and stay there for at least three days, you’ve ovulated and are in the luteal phase. This pattern is called “biphasic” since it consists of two phases.
- Wait for your period: Roughly 14 – 16 days after the day of ovulation, your temperature will drop and you’ll get your period. If your temperature doesn’t go down for at least 18 days after ovulation, you’re likely pregnant.
It’s only fair to mention that this method does require some time and patience on your part. But in saying this, it’s cheap, easy, and will give you a good sense of your cycle. It’s also a great idea to bring your notes to your doctor’s appointment since it can help to pinpoint any fertility problems.