The 6 Best Basal Thermometers

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This wiki has been updated 29 times since it was first published in October of 2016. A basal thermometer helps you detect small changes in your body’s temperature, so you can determine the best time to attempt to get pregnant. They’re more precise than standard models, since they provide readings to the hundredth of a degree. Some are also equipped with ovulation test strips, and many conveniently pair with your smartphone for automated charting and alerts. When users buy our independently chosen editorial choices, we may earn commissions to help fund the Wiki.

1. iProven BBT-113Ai

2. Femometer Vinca II

3. Tempdrop Wearable

Editor's Notes

February 24, 2020:

Today we added in the Femometer Vinca II, which features an attractive and discreet housing that resembles a tube of lipstick. Just download the compatible app to view your results conveniently on your smartphone. The app can calculate your daily conception chances by taking into account your key symptom data. It also graphs your temperature readings in order to determine your ovulation day, fertile window, safe zone, and next period date. This is an easy, practical model for anyone who doesn’t want to bother writing anything down or interpreting charts on their own. It’s also got a bright backlit LCD, an adjustable beeping volume, and durable waterproof construction that makes it easy to clean and disinfect.

The Tempdrop Wearable is conveniently worn on the arm at night to automatically read your temperature at the same time each early morning, so you won’t need to wake up before dawn just to take your temperature. It’s sold with either a standard or a large-sized band, and it also pairs with your smartphone. While there isn’t a dedicated Tempdrop app, you can sync the data to one of your choice of compatible apps. (For the full list, visit the Tempdrop website.) One caveat is that the band is light in color, so it can show dirt easily. It does come with a convenient drawstring storage pouch, and is backed by a 12-month warranty.

In this update, we also updated a couple of the selections to newer models. The iProven BBT-113Ai is very simple to use and is good for those who choose to manually enter their numbers into a fertility tracking app or onto a paper chart. The Easy@Home Smart Kit is compatible with the manufacturer’s Premom mobile app, which automatically charts your temperature and helps pinpoint telltale temperature spikes. This one comes with 25 ovulation test strips that can help indicate which days are your fertile ones. Unlike most others, the iSnow-Med High Accuracy comes with a built-in alarm clock that won’t wake the entire house, but can rouse you from your sleep to get your reading at the appropriate time. It comes with handy paper charts that you can fill in, as well as a compartmentalized storage case.

Whether you’re looking to become pregnant or to avoid pregnancy, be sure to talk with your doctor regarding the best method for you of safe and effective family planning.

Special Honors

CVS Health Basal Digital Thermometer This device provides a reading in just 60 seconds, with results shown to a hundredth of a degree in Fahrenheit. It features a flexible tip and ridges that act as a guide for proper placement in your mouth. It beeps when your reading is complete, and shuts off automatically after 30 seconds to conserve the battery. Included are a handy ovulation chart and the required CR1225 battery.

Up&Up Basal Digital Thermometer This budget-friendly choice provides a convenient 60-second readout and features a simple one-button operation. It’s lightweight and easy to use, with an audible beep to let you know when the results are in. However, note that the screen is not backlit, so you might be turning on the light in the wee hours of the morning. It features a memory recall and comes with a protective plastic case.

4. Easy@Home Smart Kit

5. Mabis Dmi Healthcare

This item has been flagged for editorial review and is not available.

6. iSnow-Med High Accuracy

This item has been flagged for editorial review and is not available.

How A Basal Thermometer Differs From A Regular One

If you only keep one type of thermometer in your home, you're better off having a basal one.

If your doctor has recommended you purchase a basal thermometer, you might be thinking, "I already own a thermometer. Why do I need to spend money on a new one?" But that thermometer you've been putting under your tongue during flu season, or even in your tea to check its temperature before drinking it, can't do what a basal thermometer can. Regular thermometers check overall body temperature to identify or keep an eye on a fever. In other words, you use regular thermometers on sick bodies. Meanwhile, basal thermometers track the minuscule temperature changes that go on in a woman's healthy body throughout her menstrual cycle. Tracking these changes helps a woman find her fertile window. Basal thermometers can do this because as a woman's hormones change at crucial points in her cycle, her basal temperature rises.

You can use a regular thermometer anytime throughout the day, whereas you can only use a basal one first thing in the morning. Another important distinction between these two kinds of thermometers is that basal models are more accurate than regular ones. Basal thermometers can be accurate to a 0.1 degree Fahrenheit variance, while regular ones are often only accurate to a 0.2 degree variance. Detecting ovulation depends on picking up on the slightest of temperature changes, whereas monitoring a fever can mean tracking significant temperature fluctuations. A 0.1 degree fluctuation in a fever isn't cause for concern, but such a change in basal temperature can be significant for a woman trying to become pregnant.

Where exactly you place each of these thermometers is slightly different, too. You can use regular thermometers orally, anally, or under the arm pit. You use basal thermometers orally, anally, or vaginally. Interestingly enough, while you cannot use a regular thermometer to track ovulation, you can use a basal thermometer to track a fever, so long as it has a large enough range. If you only keep one type of thermometer in your home, you're better off having a basal one.

What To Look For In A Basal Thermometer

Since becoming pregnant can rely on you keeping track of each and every daily thermometer reading, it is often nice to have one with memory recall. When you turn these on, they'll show you what the previous day's reading was, so if you forgot to write it down, you'll still have it. This is extremely helpful considering that you take your basal temperature immediately when you wake up, before even getting out of bed, so there is a good chance you could dose back off to sleep while waiting for the reading. That's why having a thermometer that beeps loudly when it's done can also be useful. Since your hand-eye coordination isn't at its finest first thing in the morning, you may also want a thermometer with a thumb groove or non-slip grip, just to make sure you don't drop it before getting a reading.

When picking out a thermometer, you'll have to choose between digital and glass models.

When picking out a thermometer, you'll have to choose between digital and glass models. Digital thermometers certainly have their upsides, like offering very clear readings. You don't need to squint and hold a digital thermometer close to your eyes to see the temperature reading, the way you might with a glass one. Digital thermometers also don't run you the risk of broken glass all over your floor, and you don't need to shake down a digital thermometer each night, the way you do with a glass one. Just keep in mind that you need to replace the batteries of digital thermometers. If you fail to do so, their readings may become inaccurate as the batteries begin to die or they could even shut off mid-reading.

If you wake up very early in the morning, before the sun comes up, you may not want to turn on the lights and wake up your partner to get your reading or squat down by the night light. In this case, a thermometer with an illuminated screen can be very helpful. If you travel a lot, you may not want the TSA and the rest of the world to know you're trying to become pregnant. Fortunately, there are basal thermometers with discreet designs. On-the-go women might also appreciate some of the models with advanced technology that syncs up to smartphone apps, helping them track their temperature each day without the use of pen and paper.

Tips For Using Your Basal Thermometer

If you and your partner are ready to become pregnant, you don't want to wait any longer than necessary. Even if you are keeping up with ideal sexual behavior to become pregnant, if you aren't using your basal thermometer correctly, it could all be for nothing (besides the fun, of course). Make sure to take your temperature as close to the same exact time each day. Within the same half-hour window is ideal to ensure you get dependable readings.

If you and your partner are ready to become pregnant, you don't want to wait any longer than necessary.

Having to get a reading at the same time every day can actually be a good thing if you look at it right. You can use it as the perfect excuse for you to finally get more sleep, which is important when trying to get pregnant. Studies have found that not sleeping enough can interrupt a woman's menstrual and ovulation cycle, and make it harder to become pregnant. So, go to bed and get up at the same time each day, and do your best to create a relaxing sleep environment through the use of sound machines, sleep masks, and other accessories.

It's also important that you use your thermometer the same way each time: orally, vaginally or anally. Each of these orifices can have slightly different temperatures. None are right or wrong, but it's important you're only tracking the readings from one of them. Using all of these tips in conjunction with one another can put you and your partner on the path to becoming parents more quickly.

Karen Bennett
Last updated by Karen Bennett

Karen Bennett lives in Chicago with her family, and when she’s not writing, she can usually be found practicing yoga or cheering on her kids at soccer games. She holds a master’s degree in journalism and a bachelor’s in English, and her writing has been published in various local newspapers, as well as “The Cheat Sheet,” “Illinois Legal Times,” and “USA Today.” She has also written search engine news page headlines and worked as a product manager for a digital marketing company. Her expertise is in literature, nonfiction, textbooks, home products, kids' games and toys, hardware, teaching accessories, and art materials.

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