Clearblue purple or pink: the difference explained

The difference between Clearblue purple and pink: the purple test (Advanced) shows estrogen and LH and has three symbols: an empty circle, a flashing smiley and a static smiley. The pink test (Digital) shows LH only and has two symbols, an empty circle and a static smiley, with no flashing smiley. Both are digital ovulation tests, not pregnancy tests; purple and pink are package colors, not results.

LH is luteinizing hormone. It rises sharply shortly before ovulation; ovulation is the moment when an ovary releases an egg.

Both tests work the same way: you put the stick into the holder with the display, only then hold the tip in your urine stream, and read the result there. You read only the display, not the blue stripes on the stick; according to the package insert they have no meaning.

The purple test shows two hormones: estrogen (more precisely its breakdown product E3G in urine) and LH. With the first tests, the holder works out your personal baseline and compares later tests with it. Estrogen rises in the days before the LH surge, which is why the purple test has an extra stage, the flashing smiley, before the static smiley. That stage does not decide which test suits you; it only reflects which hormones the test shows.

The pink test shows LH only, according to the manufacturer against a fixed threshold and without personal baselines. This threshold is a manufacturer’s figure, not a medical cutoff.

In everyday use, the tests differ like this:

• Urine: The purple test always needs the first urine after your longest stretch of sleep. The pink test allows any time of day, but the same time every day.
• Holder: With the purple test you need the same holder for the whole cycle.
• Start: For a 28-day cycle, the package insert says to start the purple test on cycle day 8 and the pink test on cycle day 11.
• Flashing: Only the purple test flashes. The flashing can last several days; you will then need several sticks.

If you already have a pack, follow its package insert; one of the two tests is enough for this cycle. Clearblue is the manufacturer’s brand name.

Clearblue purple (Advanced):

• Empty circle: The test shows no clear rise above your baseline. The next day you test again with a new stick.
• Flashing smiley: The test shows a rise in estrogen, not yet the LH surge. The symbol flashes day after day until an LH surge is shown.
• Static smiley: Some people also say “steady smiley” or “constant smiley.” The test shows the LH surge. It usually comes after an empty circle or a flashing smiley, but according to the package insert it can appear on the very first test day; that is not a fault of the device.

Clearblue pink (Digital):

• Empty circle: No LH surge is shown. The next day at the same time you test again with a new stick.
• Static smiley: An LH surge is shown. According to the package insert, no further tests are needed in this cycle.

The symbols describe what the test shows, not how fertile you are; and an empty circle does not mean a pregnancy is ruled out.

An ovulation test is not a method of birth control. The same goes for any calculation and observation, including the calculated days in Cyelle: a pregnancy is possible with an empty circle, and equally after a static smiley.

With the purple test, the empty circle and the flashing smiley stay on the display for about 8 minutes; with the pink test the result stays on for about 8 minutes as well. If you missed it and the stick is still in the holder, you eject it with the eject button. The result then appears again for about 2 minutes.

The static smiley of the purple test is the exception: it stays on for 48 hours straight, and in that time the holder reads no further test. That is a display duration. A smiley that is still showing the next day is therefore not a second surge.

If you keep testing after the static smiley anyway, the holder shows “New cycle.” That is not an error message. The package insert advises not to keep testing after the first static smiley in a cycle. That concerns only testing, not the question of when a pregnancy is possible.

With the purple test you wait 5 minutes, with the pink test up to 3 minutes, with the stick in the holder. If an error symbol appears, the package insert explains what it means. Usually you repeat the test with a new stick; with some errors the holder can no longer be used, and then you need a new pack. You never reuse a used stick.

When you start with Clearblue depends on your cycle length. Cycle day 1 is the first day of full bleeding, not spotting before it. Cycle length counts from day 1 to the day before your next period. You read your start day from the table in the instructions: in the column with your cycle length, you find the day on which you start.

An example with the same length: for 28 days, the package insert says to start the purple test on cycle day 8 and the pink test on cycle day 11. For short and long cycles, these rules apply:

• Cycle of 21 days or shorter: day 5 for both tests.
• Cycle of 41 days or longer: for the purple test 20 days, for the pink test 17 days before your next expected period.

If your length varies, both package inserts use the shortest of your last six cycles (for the pink test: of the last six months, as soon as the length varies by more than 3 days). If you don’t know your length, track for at least one cycle when your period starts. The pink package insert gives day 10 as a fallback and notes that you can then miss the surge.

The numbers come from package inserts, which can change; the table on your pack is what counts. You don’t have to use up all the sticks: after the static smiley you can stop, and you may use leftover sticks and the holder in the next cycle.

Morning or evening depends on the test. The purple test always requires the first urine after your longest stretch of sleep, because its baselines are calibrated to it. With morning urine, the 4-hour break from urinating is usually already met by the sleep. If you missed the first urine, the package insert says to test as soon as possible and drink normally; a flashing smiley can then appear unexpectedly.

Until the flashing smiley appears, you test once a day. After that, the package insert says you may test more often; it doesn’t say how often, and before each test the 4-hour break applies again.

The pink test allows any time of day, but the same time every day. Many people choose the morning because it is easy to remember. Here too: no urinating for 4 hours beforehand.

With both, you drink normally, neither a lot nor a little; the package inserts speak of normal amounts of fluid.

According to the package inserts, these mistakes lead to error symbols or unexpected displays:

• Putting urine on the stick before it is in the holder, or holding the tip pointing up.
• Taking up too much or too little urine, or ejecting the stick too early.
• Urinating less than 4 hours beforehand, or drinking a lot.
• Switching holders with the purple test, or removing the batteries. You remove the batteries only when you no longer need the holder.
• Reading the result from the blue stripes instead of the display.

“Purple positive, pink negative”: that is how many people ask. Positive and negative are not words on the display. If the purple test flashes and the pink one shows an empty circle, that fits together: the purple test shows estrogen, the pink one only LH, and the LH surge has not started yet.

It is harder when the purple smiley is static and the pink circle stays empty. That can also come down to the devices: according to the manufacturer, the pink test works with a fixed threshold, while the purple one compares with your baseline, and the testing times differ too. Classic test strips often follow yet other rules. No test is the yardstick for another, and each shows only a moment.

For this cycle, the package insert of the test you started applies. If you use several in parallel, log each result separately, with the time, rather than weighing one against the other.

Ovulation tests can also miss a surge, for example if it falls between two tests. The laboratory accuracy figure printed on the pack describes how reliably the test picks up LH in a lab sample. It does not say how precisely ovulation can be predicted.

How many days the purple test flashes before the static smiley comes varies a lot. According to the manufacturer, based on a small study, it is zero to four days for about two in three women, five to nine days for about one in four, and ten or more days are very rare. If it has been flashing for five days, that is within the range the manufacturer describes.

In about 8 in 100 women in this study, no static smiley appeared at all after the flashing. The manufacturer calls this not unusual; only a medical exam can clarify the reason. A missed test can also hide the surge.

If the smiley flashes for more than 9 days even though you started on the right cycle day, you can stop testing for this cycle: according to the package insert, a static smiley is then probably not coming. You start again in the next cycle. With long flashing, several sticks are needed.

If you haven’t tested for 3 days or longer, the purple test shows “New cycle.” If no static smiley follows, the package insert advises waiting for the next cycle. If the test shows an empty circle again after the flashing, the package insert does not describe this case; log what the display shows every day, and ask your ob-gyn’s office if you have questions.

If the static smiley fails to appear in three cycles in a row (for the pink test: no smiley), the manufacturer says this is best looked into medically. The test cannot say why it is missing; only a medical exam can clarify that.

After the static smiley, ovulation follows about 24–36 hours later, according to the manufacturer. Other expert sources give 12–36 hours, in individual cases up to about two days. That is a range, not a point in time. The static smiley means the test shows an LH surge, not that ovulation has already happened.

A pregnancy is most likely in the days before ovulation and on the day of ovulation itself. According to expert sources, sperm survive 3–5 days, and the egg can be fertilized for about 12–24 hours. So for a pregnancy, a period of time counts, not a single moment.

On top of that: in a study with lab LH values, about 3 in 10 cycles showed a brief LH rise before the rise that ovulation followed. So a rise does not prove that ovulation follows right away. How often this happens with the thresholds of the Clearblue tests, the package inserts do not say.

An ovulation test shows neither a pregnancy nor the absence of one; the smiley has nothing to do with the displays of a pregnancy test. A pregnancy test before your expected period can still be negative despite a pregnancy. If your period is late, you take a pregnancy test, not another ovulation test.

You log what your display shows, and Cyelle saves your entry, without a photo. That applies to both Clearblue tests.

You can log several tests a day, each with its time. If you want to change an entry, you delete the row in “My entries” and log the test again. If you also use test strips, you log them separately; in Cyelle they appear in separate lists and statistics.

If you log a static smiley, Cyelle sets the predicted ovulation to the following day and aligns your calculated fertile window with it, meaning the days on which a pregnancy is calculated to be most likely. It remains a calculation from your entry, not a measurement. The flashing smiley changes nothing; reminders you have turned on do not change because of an entry.

Certain circumstances can make the display misleading. For both tests, the package inserts list:

• a pregnancy, or one that ended only recently,
• menopause,
• medications that contain LH or hCG,
• other medical conditions.

Only the package insert of the purple test additionally lists certain antibiotics and reduced liver or kidney function. If a pregnancy has ended, your ob-gyn’s office will go over with you when a test is meaningful again.

In these cases the display says less. That is down to the circumstances, not to you. For unexpected results, it is best to ask at your ob-gyn’s office or a pharmacy; the package insert and the information sheet of your medications help with that. If you are in fertility treatment, what your clinic tells you applies.

After stopping birth control pills or other hormonal birth control, both package inserts advise waiting two cycles, because your cycle can be irregular afterward; the pink package insert additionally advises noting the length. According to the pink package insert, stopping does not change the display itself, it only makes it harder to calculate the test start. The purple package insert says the same after a pregnancy that ended only recently. How long that applies to you, you clarify with your ob-gyn’s office. That concerns only when to start testing, not the question of when a pregnancy is possible.

It can take several months for a pregnancy to happen, and the wait can weigh on you. As guidelines for a medical conversation with regular sex without birth control: under age 35 after 12 months, age 35 or older after 6 months, age 40 or older right away.

You don’t have to wait for these time frames if you have questions sooner. If your period is very irregular or absent, or if a pregnancy ended earlier, you can ask at any time. Causes can lie with one or both people; the doctor’s office explains what the work-up involves.

If the wish for a child weighs on you heavily, talk about that as well at your ob-gyn’s office or with a midwife.