Are you still using the temperature method to track ovulation?



Problems with the Temperature Method

Monitoring your basal body temperature (BBT) is probably the first way you started tracking ovulation and your fertile window. The method has been around since our moms were getting pregnant, and it’s backed by science, so we trust that it works. But is it really a good method for figuring out the best time to try to make a baby? We don’t think so. Here’s why:

BBT is influenced by many other factors besides ovulation. Sleep later than normal? It could affect your BBT. Have a little too much to drink last night? It could affect your BBT. Wake up to pee in the wee hours of the morning? It could affect your BBT. Heat wave? It could affect your BBT. See a pattern here?
Even if you’re super diligent about taking your temperature and you manage to see a clear BBT rise on your chart, it’s already too late to conceive that month. Your BBT rises after ovulation, when you’re no longer fertile.

If you have very regular cycles, you can use last month’s BBT rise to estimate when next month’s fertile window might be, but this is only an estimate. For many women—especially those with irregular cycles—this prediction may not be accurate.

Contrary to popular belief, BBT doesn’t always rise immediately after you ovulate. According to a study that compared BBT readings with ultrasound—the gold standard in confirming ovulation—only 11 percent of women have a BBT rise within one day of ovulation. For many of the women in the study, BBT did not rise until more than two days after ovulation.

Practically, this means that 89 percent of women using BBT are identifying the wrong ovulation day. If you’re using BBT to time intercourse, you may over- or undershooting your fertile window by several days and reducing your chances of conceiving.

BBT charting is a decent way of retrospectively confirming ovulation at the end of your cycle, but it’s not very good at pinpointing exactly when it happened.

If taking your temperature every morning were effortless, that would be one thing. There’s nothing wrong with having another possible datapoint about your fertility. But the truth is, most women find it extremely burdensome. Who wants to get woken up with an alarm at 6:30am every day reminding you to stick a thermometer in your mouth (or your butt, if you want a really accurate reading?!)? Who wants to worry about waking up their partner when the thermometer beeps? Who wants to hold in your pee so you don’t mess up your temperature reading?

Not us!

his gets into a larger issue, which is the expectation that women do all the work when it comes to fertility and baby-making. When it’s time to get pregnant, women are the ones peeing on sticks, asking google about the quality of their cervical mucus, taking their temperatures, and sometimes getting invasive fertility treatments.

All men have to do is ejaculate. Not a fair deal!

It’s cool that charting your BBT can give you insight into your body, but for the limited information it gives you, it just doesn’t seem worth it to us.

Ava is a sensor bracelet, worn only at night, that detects subtle physiological changes that are associated with changing hormone levels throughout the menstrual cycle. It was shown in clinical trials to detect an average of 5 fertile days per cycle in real time—more than any other method, including BBT charting and OPKs. The reason it’s able to detect that many days during the current cycle is because it doesn’t only track temperature. It also tracks physiological changes that happen when estradiol rises, usually five days before ovulation.

Meet Ava

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“If women can get an advanced heads up on when they’re going to ovulate, they’re more likely to be able to conceive.” – The Verge
“The wrist-worn device identifies fertile days. The average is identified as five per cycle, which is about two more than most other methods. This nearly doubles the wearer’s chances to conceive.” –
“Rather than only looking at a single factor of ovulation, like a urine ovulation test or the basal thermometer, the Ava has sensors that track nine different biological parameters.” –
“Unlike many other fertility trackers, its makers say Ava can tell you when you’re most fertile in real time, while most methods that use temperature and cycle-tracking alone work only in retrospect.” – New York Magazine
“Ava is different, giving users something that works like a fertility Fitbit — and it’s just as easy as your fitness tracker to use.” – BabyCenter
“Even if you’re not thinking about starting a family anytime soon, knowing when you’re fertile can be a really empowering thing.” –
“The bracelet uses technology to solve one of the more frustrating problems for some couples: getting pregnant.” – CNET
“I’m really intrigued by Ava, the first FDA-approved fertility tracking bracelet that could be a huge game changer for women (and couples) trying to get pregnant.” –
Ava Fertility Tracker

Ava is a fertility tracking bracelet that identifies an average of five fertile days per cycle, doubling your chances to conceive. There’s no guesswork around timing intercourse or tracking ovulation. Wear Ava at night and the rest is taken care of—all that’s left for you to do is the fun part.

Whether you’ve just started trying to conceive or your fertility journey is taking longer than you expected, Ava can help. It gives you the confidence to always know you’re trying at the right time, and the convenience to not have to think about it too much. Ava makes for a better, easier, more magical journey to conception for you and your partner.

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Ava lets you see the big picture of your fertility window in a way that a urine test just doesn’t.
Jessica W., age 29
I’ve used other cycle trackers, but Ava was the only one where the fertile window perfectly matched up with my cervical mucus.
Teresa G., age 32
I used to do BBT, and the results were so confusing. With Ava, it’s so much clearer.
Abby G., age 26
Ava takes the guesswork out of tracking my cycle.
Priyanka D., age 36

What Makes Ava Different

It’s smart.

While you sleep, Ava’s sensors gather physiological data points to detect your fertile window.

It’s convenient.

Throw out your BBT thermometer and stop peeing on sticks. Wear Ava at night, and the rest is taken care of.

It gives you time.

Ava gives you in-cycle, real-time detection of five fertile days, so you and your partner can relax and enjoy the babymaking process knowing you are trying at the right time.

70 percent of pregnancies happen in the same three cycle days, and with Ava, it’s never been easier to find the fertile days in your cycle.

With Ava, You Can…

  • Double your chances to conceive every month
  • Get five fertile days per cycle
  • Enjoy your entire fertile window with your partner—no need to rush.
  • Monitor your general health and wellness while you’re trying to conceive and throughout your pregnancy
  • Gain insight about your menstrual cycle
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What Ava Measures

Pulse rate is an accurate estimation of how often your heart beats per minute (bpm). Typical resting pulse rates for adults are between 40 and 80 bpm, but if you get a lot of aerobic exercise, your resting pulse rate may be lower.
The temperature of your skin at your wrist. Even though your wrist skin temperature reading is lower than your oral temperature reading, it still provides a strong indication of your basal body temperature (BBT). During the night, your wrist skin temperature rises and your core body temperature falls. Both your core temperature and your wrist skin temperature rise by about one half of one degree Fahrenheit after ovulation.

Average skin temperature reading (when taken at room temperature of 64.5 – 77 degrees Fahrenheit) are between 90.68 and 98.24 degrees Fahrenheit. If you sleep in a room warmer than 77 degrees Fahrenheit, it could cause your skin temperature to go up.

HRV is the variation in the time interval from one heartbeat to the next. It can be used as an indicator of physiological stress.

Most people think of heart rate as the average number of beats per minute, but your heart rate changes from beat to beat. HRV measures this naturally occurring irregularity in heart rate. The more variation in the interval between beats, the lower your physiological stress level.

Ava measures the ratio between low frequency and high frequency waves in your heart rate. Scientific studies have shown that the HRV ratio is a good indicator to assess the balance between the sympathetic nervous system and the parasympathetic nervous system. An imbalance in these systems—usually when the sympathetic branch takes the upper hand—is associated with high physiological stress level and results in a high HRV ratio.

Estrogen and progesterone have an impact on HRV. The HRV ratio is increased during the luteal phase when progesterone peaks, compared with the follicular phase, when estrogen is high.

Normal HRV ratio varies widely from person to person, but by looking for an increase or decrease from your baseline HRV ratio, you can learn about your body’s physiological stress level. HRV ratio is complicated, but the important thing to remember that a higher HRV ratio indicates higher stress.

The quality and amount of sleep you’re getting each night are important parameters to track for your fertility. Your menstrual cycle can affect your sleep, and your sleep, in turn, can affect your menstrual cycle. Ava shows the total amount of sleep you get each night. This doesn’t count time you might spend reading in bed; the bracelet can distinguish between sleeping and lying quietly. It also tracks the percentage of light sleep and the percentage of combined deep and REM sleep.

Average percentages for adults are 47 – 60 percent light sleep and 33 – 48 percent deep sleep + REM.

Rate of respiration per minute.
Ava tracks your movement with an accelerometer. This parameter allows the bracelet distinguish between light and deep + REM sleep.
Perfusion describes the process of supplying blood to the tissues of your body. As blood flows through your capillaries, it delivers nutrients to the tissues and helps sweep away waste. Then, the blood flows back to the heart, and begins the process all over again.

If you’ve ever had an elastic band around your finger and felt the blood flow being cut off, you’re already familiar with the process of perfusion. While you can limit perfusion with an elastic band, perfusion can also change naturally for different reasons. For example, your perfusion changes in order to keep you warm or cool you down. Estrogen and progesterone also have an influence on perfusion. Estrogen increases perfusion, while progesterone has the opposite effect.

Bioimpedance measures the resistance of body tissue to tiny electric voltages. If you’ve ever measured your body composition such as fat content, this is very similar. Besides analyzing fat content, bioimpedance provides information about the skin, including hydration and sweating patterns.

As you have probably observed throughout your life, reproductive hormones have an impact on your skin. Your skin can change at different phases of the menstrual cycle, during puberty, and during pregnancy.

Heat loss is closely related to the onset of sleep. As you lose heat through your hands and feet, your skin temperature increases and your core body temperature decreases. This heat loss is closely related to the onset of sleepiness.

Heat loss is also related to your metabolic rate. The mechanism for the maintenance of the higher temperature during the luteal phase is still a matter of scientific discussion. Some researchers believe that reduced heat loss is responsible, while others believe that higher internal heat production (increased metabolic rate) is the cause.

The Science Behind Ava

Ava completed a year-long clinical study at the University Hospital of Zurich under the lead of Prof. Dr. Brigitte Leeners, a leading expert on the mathematical modeling of menstrual cycles. Ava was found to identify an average of 5.3 fertile days per cycle with an accuracy of 89 percent.

The results of the study were presented in June 2016 at the Swiss Society of Obstetrics and Gynecology Annual Congress and will be presented in October 2016 at the German Society of Obstetrics and Gynecology Annual Congress. Bayer, the leading women’s health company, is sponsoring Ava’s presentations.

Our scientific research paper will be submitted in summer 2016. We expect it to be published by a peer-reviewed journal in reproductive health by the end of 2016.

Learn more about how Ava works.

Ava Works Throughout Pregnancy

With Ava, you’ll get vital details about your health not available through any other app. Wear Ava at night during your pregnancy to track your sleep quality, stress levels, and resting heart rate. And if you plan to have more children, you’ll have Ava to help you conceive for your next pregnancy.

Get Your Ava

Ava Fertility Tracker

Take charge of your conception with Ava. No other method of fertility tracking gives you 5 in-cycle fertile days while also providing insight about sleep, stress, and resting heart rate.

If you become pregnant or change your mind at any time before Ava ships, contact us and we’ll cancel your order, no questions asked.

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