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Babyndex app and microscope


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Find out when you are most likely to get pregnant.

It is easier to get pregnant two days before ovulation than on the day of ovulation. There are tests that can tell you when ovulation is happening but it is more important to know the days leading up to it.

What is Babyndex?

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Apply a very little saliva to the lens of the microscope that we supply and wait for it to dry. Saliva starts to crystalize when you hit your fertile window.

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Download the application on your smartphone, hold the microscope against the camera and take a picture of the saliva sample. The app recognizes the saliva crystals.

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You can find out when there is a high chance of getting pregnant. Our algorithm analyzes the saliva patterns and determines the probability of crystals.

Is Babyndex right for you?

The saliva ovulation test only works if you are not using hormonal birth control. If you have PCOS, your crystals may be different but the test may still show your actual fertile days. Also, if your cycles are irregular, the test may show your actual fertile days.

When you’re not pregnant, estrogen levels rise before ovulation, which makes the cervical mucus fertile and dried mucus and saliva may form a fern-like pattern, then one or more eggs are released from the ovaries each month.
When you are pregnant, your body produces progesterone, which prevents this process. Hormonal contraceptives also contain progesterone, which prevents the cervix from producing fertile mucus and the ovulation.
Babyndex helps you identify your most fertile days by detecting crystal patterns formed by your saliva only if you are not taking hormonal contraceptives. You should not use this test to help prevent pregnancy, because it is not reliable for that purpose.

Polycystic ovary syndrome is the most common hormonal disorder. The level of estrogen may be consistently high and the eggs may not be released from the ovaries. With PCOS, the saliva may form different patterns than usual. Hence the test may be less accurate in detecting your fertile days. However, you can try it and see how the saliva crystal patterns change over a full cycle. If it does not work, please send the microscope back and we will return its price.

With irregular cycles, ovulation prediction is close to impossible with common urinary LH and basal body temperature tests. However, the cervix, cervical mucus and saliva may show the actual signs of fertility. The fern-shaped crystals in your dried saliva sample indicate your most fertile days prior to ovulation. Of course, it does not mean that you will definitely ovulate or become pregnant. If you cannot see saliva crystals during a whole cycle, please send the microscope back and we will return its price.


Why is Babyndex so special?

Conception does not always lead to pregnancy. The saliva ovulation test shows your actual and most fertile days, when you have the highest chance of getting pregnant. The probability of conception is similar in the last 3 days of the fertile period. However, conception 2 days before ovulation is 3-5 times more likely to lead to clinical pregnancy. The saliva test can show you the most fertile days for getting pregnant.

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Probability of conception
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Probability of pregnancy

Babyndex is the first mobile app that combines the saliva ovulation test with modern technology to recognize saliva crystal patterns. With the ovulation microscope you can magnify the saliva samples and with the app you can recognize the fern-like saliva crystals. Babyndex also stores the results in a secure and convenient way. Knowing where in your ovulation cycle you are can improve your chances of getting pregnant not only of conceiving. Babyndex can help you get pregnant sooner!



Your saliva crystallizes during your fertile days. Hence women with irregular cycles can also use Babyndex. There is no need for months of body temperature data.



A 2018 study by Harvard Medical School showed that saliva test can predict ovulation with more than 99% accuracy with automated crystal detection.



You can use Babyndex as many times as you want. This environment friendly fertility monitoring is more affordable than single-use hormone stripes.

full ferning

What is the saliva fern test?

This test can be used to help you plan to become pregnant. Your saliva crystalizes during your fertile days before ovulation. Your body goes through different stages of your ovulation cycle. When the estrogen hormone levels increase and cause that saliva starts to crystalize.

If you put some of your saliva on a lens, allow it to dry, and look at the pattern it makes, you will see dots and circles, a fern (full or partial), or a combination depending on where you are in your monthly cycle.

These saliva crystals resemble the shape of fern leaves and the whole procedure is also called saliva fern test. You need a high-quality microscope to detect these crystals. Just try it!

How reliable is the saliva test?

Harvard Medical School studied the effectiveness of the saliva ovulation test combined with automated crystal detection in 2018. The Harvard researchers have concluded that the accuracy of the same solution as Babyndex is higher than 99%. Using this method, we detect estrogen hormone increases in a less intrusive and more affordable way than comparable urine or electrolyte tests. What is more, FDA has already approved saliva test for ovulation prediction, which is what Babyndex is also based upon.

How to detect the fertile days?


Urine LH test


Saliva ovulation test


Basal body temperature test

The saliva fern test can show you the most fertile days and the Babyndex app you can help you interpret the saliva crystals. The microscope is reusable and affordable. The test is non-invasive and the results show the actual fertile window with an extremely high accuracy of >99 %.

Take the test every day for a full cycle!

Babyndex is easy to use. Make testing your morning routine. Remember to take the test every day for full cycle! Then you can take it regularly during the expected fertile phase. This is how you can get the best results for detecting your fertile days and for getting pregnant.

What our customers say

Who invented Babyndex?

My name is Ákos Bodó, I am an OB-GYN and the co-inventor of Babyndex. I have been helping women with fertility issues for over 50 years. Are you interested in your actual fertile window? Babyndex might help you. During the fertile days, the structure of body mucus changes and dry saliva crystallizes. We have built an application to help you detect these saliva crystals. Plus, we thought it would be necessary to write about actionable tips on how to improve fertility and to reach your desired goals.

So welcome to this exciting journey!

Inventor of Babyndex

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*Running on iOS 11.0 or later and Android KitKat or later

Patent US 11,583,260

Ways to buy Babyndex

Ordering, Payment, Shipping and Refund

Ordering is without registration.

Payment is via bank card, PayPal and Cash on Delivery for an extra fee.

Shipping is estimated in 1-5 business days in Europe.

If saliva ovulation test is not working for you after having used it for a whole cycle, please return the microscope and we will refund its price.

CE Certification:

Maybe Baby is a Mini Microscope for Ovulation Cycle Observation and bears the CE marking that indicates conformity with health, safety, and environmental protection standards for products sold within the European Economic Area.

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