Fertility Monitor

Clearblue Fertility Monitor

The Clearblue Fertility Monitor is the most advanced home method, proven to almost double the chances of conceiving*. It detects changes in two key fertility hormones, luteinising hormone (LH) and estrogen, to display your fertility status every day. It will typically highlight 6 fertile days each cycle, that’s more than any ovulation test – to help you get pregnant sooner.

Proven to increase the chances of getting pregnant naturally by 89%

Proven to increase the chances of getting pregnant naturally by 89%1

In a study, women using the Clearblue Fertility Monitor had a better chance of conceiving than women not using the Monitor.

Shows typically 6 fertile days

Shows typically 6 fertile days

It identifies typically 6 high and peak fertility days, more than any ovulation test, and therefore shows you more days where you have an opportunity to conceive.

Stores your unique data

Stores your unique data

By recording your hormone data, the Fertility Monitor tells you when to test according to your unique cycle profile and will also warn you when your next period is due, so you can test for pregnancy.

99% accurate in detecting the LH surge

99% accurate in detecting the LH surge

Accurately compares to ultrasound in predicting ovulation2

Easy to use and personalised

Easy to use and personalised

Unmistakable display of your personal fertility every day


Which sticks you can use with Clearblue Fertility Monitor

  • Clearblue Advanced Fertility Monitor
    Fertility Tests
    Read more
  • DO NOT USE Clearblue Advanced Fertility Monitor Pregnancy Tests
    Read more
  • Clearblue Fertility Monitor Fertility Tests
    Read more

How to use Clearblue Fertility Monitor

  • 1. Doing the test when requested

  • 2. Wait for 5 minutes

  • 3. Read your results

What do other people think?


"After a year of trying to conceive I bought the CB Fertility Monitor, I got pregnant at my first cycle using it and had a son. I then used it again when we were trying for number 2 – I got pregnant on the 2nd cycle and had my daughter in May! Thank you Clearblue – best money I ever spent!"


"I just wanted to say, that I think this product is amazing, I used it after struggling to conceive for 4 years. I am now using it again to help with conceiving baby no:2. thank you so much."


"I just wanted to write a note to say a great big thank you. I purchased the Clearblue fertility monitor and test sticks in November 2011 ahead of my next cycle in December 2011. I've found out I'm pregnant and over the moon. Thank you so much for all the wonderful products you create, we were so lucky for the monitor to work first time for us and after 3 months of trying this was the perfect product for us and I would highly recommend it to anyone. Our baby is due on 10th September 2012 and it's all thanks to Clearblue. Thank you for providing a great service."


"I am very satisfied of using the Clearblue product. I must say that I was trying to be pregnant normally for 9 months with no results. After the 9 months passed it came from my mind to continue my efforts by making IVF. At the same moment I was informed from an internet site about Clearblue Fertility monitor and it looked very interesting so I decided to give a last chance to a normal pregnancy than an IVF. I ordered it through a foreign internet site, because I couldn’t find it in Greece. I used it and followed its results and I am very happy to announce to you that at this moment I am 10 weeks pregnant and I informed most of my friends how helpful and simple were to use this product and also that it worth the money!"

"I tried everything and I think that Clearblue fertility monitor is a very smart product and I think that it will help and other women as it helped me."

K, London

I bought a CBFM and we got pregnant the 1st attempt :-) My cycles are not your typical 28 days, they vary from 32 - 35 so my husband and I didn't really know when I was ovulating. The CBFM worked wonders - thank you ! I also bought the CB PLUS tests and they showed positive 2-4 days before my period was due. Roll on April for our little bundle of joy to arrive !! Thank you :-)

Frequently asked questions

? Is Clearblue Fertility Monitor suitable for me?

The Clearblue Fertility Monitor is suitable for you if your natural cycle normally lasts between 21 and 42 days. The majority of women will need 10 Test Sticks in each cycle. Women with irregular or long cycles may have to use 20 Test Sticks each cycle in order to detect their most fertile time. Certain medical conditions and medications can adversely affect the performance of the Clearblue Fertility Monitor. If you have menopausal symptoms, polycystic ovarian syndrome, impaired liver or kidney function, or if you are pregnant or have recently been pregnant (even if not carried to full term), you may get misleading results. You may also get misleading results if you are using antibiotics containing tetracyclines, hormonal treatments (e.g. hormonal contraception, hormone replacement therapy), fertility treatments containing human Chorionic Gonadotrophin (hCG) or Luteinising Hormone (LH), or any treatment that might affect your cycle. If you’re taking clomiphene citrate, we advise you to consult your doctor for advice before using the Clearblue Fertility Monitor. Clomiphene citrate can raise estrogen levels and this may result in High Fertility being declared early in the cycle and more High Fertility days being displayed, and in some cases the Fertility Monitor may not show Peak Fertility even when ovulation occurs. If you’ve recently been breastfeeding, using hormonal treatments (e.g. hormonal contraception, including emergency contraception, fertility treatments, hormone replacement therapy), or any other treatment that might affect your cycle, you should wait until you’ve had at least two natural menstrual cycles in a row (each lasting 21-42 days), before using the Clearblue Fertility Monitor. Similarly, if you have recently been pregnant (even if not carried to full term) we advise you to wait until you’ve had at least two natural menstrual cycles in a row (each lasting 21-42 days) before using the Clearblue Fertility Monitor. This is to ensure that the results are not affected by any hCG you may still have in your body just after pregnancy. Please speak to your doctor if you need further advice. Please Note: There are no products available that can guarantee success in achieving pregnancy. The Clearblue Fertility Monitor is designed to help you become pregnant and is NOT intended to be used for contraception. Some medications are contra-indicated in pregnancy and we therefore recommend that you consult your doctor if you are taking any medication before you try to conceive. Couples with medically diagnosed fertility problems should consult their doctor before using this product.

? How accurate is the Clearblue Fertility Monitor?

The Clearblue Fertility Monitor has been shown in laboratory testing to be 99% accurate in detecting the LH surge in cycles in which an LH surge had also been identified by a reference method.

My Clearblue Fertility Monitor did not display a Peak Fertility symbol this cycle. What does this mean?

There may be a small percentage of cycles in which you do not see Peak Fertility status. Possible reasons for this are, for example, a test may have been missed or performed incorrectly or you may not have ovulated this cycle. An unusually short or long cycle may result in Peak Fertility not being detected. If Peak Fertility is not detected, the Fertility Monitor may show High Fertility for an extended period of time (up to 19 days). If this occurs, it is unlikely that you will be fertile during this entire time. If after completing 3 cycles you have not seen Peak Fertility we would recommend that you speak to your doctor.

My Clearblue Fertility Monitor displayed Low Fertility during all of my last cycle. What does this mean?

The Fertility Monitor did not detect the necessary change in the hormones that control your fertility. You may not have ovulated during this cycle or it may be due to a missed test, or a test being performed incorrectly. If after completing 3 cycles your Fertility status is only ever Low, you should speak to your doctor.

My Clearblue Fertility Monitor changed straight from Low to Peak Fertility this cycle. What does this mean?

This may happen for example when a rise in estrogen is detected on the same day as your LH surge or if the Fertility Monitor does not detect a change in your estrogen before your LH surge. This can happen if you miss a test, or perform a test incorrectly, or if you have a very short cycle following longer cycles.

Can I use Clearblue Fertility Monitor Test Sticks from different packs?

No. Always use Test Sticks in sets of 10 from the same pack (LOT). The Clearblue Fertility Monitor works by comparing the current day’s test reading with those of previous days. As there are slight sensitivity differences between Test Stick LOTs, optimal performance is achieved when the Test Sticks are used in sets of 10 from the same LOT. After carrying out your first 10 tests, the Fertility Monitor may request a further 10 tests in the same cycle. If you do not have any more Test Sticks from the same LOT, then you may use 10 Test Sticks from a different LOT to complete your testing.

How do I use the Clearblue Fertility Monitor if I work night shifts or travel between time zones?

Ideally you should set your ‘m’ Button so that your Testing Window permits you to test using your first urine after waking, which may be in the afternoon. If your sleeping pattern changes temporarily during your testing period, you should collect a sample of your first urine upon waking. You should store the collected urine and check your Fertility Monitor during your next Testing Window and, if you need to do a test, use the collected urine. (Refer to question 17 in the full instructions for use on testing with collected urine.) Download an instruction booklet here.

Can the information in the Clearblue Fertility Monitor’s memory be lost?

The Fertility Monitor retains data from your last six cycles. This data is constantly overwritten as you continue to use the Fertility Monitor to ensure it has the most up to date information available.

Can I stop using the Clearblue Fertility Monitor and start again in the future?

Yes. Remove the batteries. Store the Fertility Monitor in a dry place. For instructions on resuming use of your Fertility Monitor refer to page 30 in the full instruction booklet. Download an instruction booklet here.

I have been using Clearblue Fertility Monitor for several cycles and have still not become pregnant. Why not?

Conception is a complex biological process and there are many influencing factors. It can take many months to become pregnant. If you have not conceived after 6 consecutive cycles or you have other concerns, you should consult your doctor.


Quiz time!

Test your knowledge on ovulation, the menstrual cycle, and fertile days with this 2-minute quiz (10 questions).


How to get pregnant faster?

Having sex at the right time of your cycle is key, so identifying your fertile days with an ovulation test will help you get pregnant faster.