Ovulation tests: what they are, how they work and when to start doing them -

Ovulation tests (or ovulation sticks) are a method of predicting ovulation in advance and therefore having targeted intercourse to conceive a child. Here’s how they work and how to use them without making mistakes.

The ovulation test is a device that helps identify the fertile days of the menstrual cycle by detecting changes in hormone levels in the urine. The use of ovulation tests is useful for increasing the chances of pregnancy and is particularly recommended for women who cannot recognize the fertile period from the analysis of the cervical mucus or from the typical symptoms of ovulation.

In particular, there are two main types of tests:

those that identify luteinizing hormone (LH) , such as Canadian tests , Femometer tests , and LH tests ;
those that detect both LH and estradiol , such as Persona® tests and Clearblue® dual hormone indicator tests .

In this article, we will see in detail what they are, how they work, how to read the results and when to have reports based on the results obtained.

Table of Contents

Canadian Ovulation Tests, Femometer Tests and LH Tests

These ovulation sticks work by identifying the peak of the LH hormone , the hormone which determines the release of the egg cell (oocyte) from the ovarian follicle, i.e. the moment of ovulation .

They have a colored part , which represents the handle of the stick, and an absorbent part , which must come into contact with the urine (in a container or under the stream, for the time indicated on the package).

Holding the test with the handle in the right hand, the first band on the right is the control line and the other is the hormone detect line .

How are they used?

Ovulation sticks are not used like common pregnancy tests . Therefore, before you start using them, it is important to carefully follow the manufacturer’s instructions.

In general, it is not recommended to use the first morning urine (unless specifically indicated on the packaging), as is usually the case with pregnancy tests. The hormone LH begins to be produced early in the morning and becomes detectable in the urine about 3-6 hours later.

Therefore the best time to do ovulation tests is around lunchtime, i.e. with the second pee in the morning.

Ovulation test: when is it positive?

The result of the test sticks must also be interpreted differently from pregnancy tests.

In fact, the ovulation test is positive if and only if two lines of equal intensity are visible or if the LH line is more evident than the control line.

Conversely, the test is negative when only the control line appears or if the LH line appears but is of lower intensity than the control .

A hormone line that is lighter than that of the control, therefore, does not represent a positive result.

If you don’t see any lines

The test is invalid if no control lines are visible .

Canadian ovulation tests : advantages

Canadian tests are the cheapest solution and therefore allow you to repeat the test even several times a day to identify the hormone peak.

Femometer ovulation test : advantages

These tests work identically to Canadian tests in that they read the hormone LH. However, many women use Femometer ovulation tests in conjunction with an app that reads the two lines and makes the results easier to read.

The app isn’t required to detect ovulation, but it can be helpful for beginners. In any case, the test is always positive and in any case only if the two lines are equal.

Positive ovulation test: when to have intercourse?

It is essential to have intercourse already on the first day of the positive test if you have not had intercourse in the previous days. In fact, it is generally recommended to have intercourse every other day from the moment you start to notice fertile cervical mucus .

The production of fertile cervical mucus or in any case the sensation of wetness in the vagina is linked to the increase in estrogen that occurs before the LH peak.

Furthermore, it is always better for the oocyte to find the sperm ready to wait for it as after ovulation it degenerates with the passing of the hours and survives a maximum of 12-24 hours.

To properly target your reports you need to know that:

from the moment of the beginning of the increase of LH in the blood to ovulation 35-44 hours pass ;
the LH surge in the blood precedes ovulation by 10-12 hours;
the LH hormone begins to increase mainly between midnight and early in the morning, so it is preferable to have intercourse as soon as we notice that the LH line begins to intensify ;
all we detect with the ovulation test is the outcome of what happened 3-6 hours earlier in our body.

When in doubt, in order not to lose the LH peak and useful hours to try to conceive, the Canadian tests can be done a couple of times a day (being very cheap), perhaps 12 hours apart from each other.

Ovulation test LH and estradiol

These are the Clearblue® Purple Dual Hormone Indicator Tests and the Persona® Tests . These tests read both LH and estradiol and thus pinpoint a total of 4 fertile days . In this way there is no risk of discovering a positive ovulation test too late and there is plenty of time to have intercourse in the period of maximum fertility of the cycle.

Clearblue Ovulation Test: When to Have Intercourse?

Clearblue Dual Hormone Indicator tests show a flashing smiley when estrogen increases . This result can appear two to six days before the LH surge. Subsequently, the flashing smiley will be replaced by a solid smiley indicating the increase in LH hormone.

The advice is to start having relationships as soon as the flashing smiley appears.

Test Persona: when to have intercourse?

Personal Ovulation Tests can be used with or without a monitor. Using the monitor everything becomes easier, but you can save a lot by learning to interpret the lines: you become very good in a few test cycles.

If you use the Person Without Monitor Ovulation Tests you need to learn to interpret the left and right line.

The right window is that of LH, the left one of estradiol ( what are these hormones? ).

Fertility is greatest when estrogen is high (and therefore we also produce a lot of fertile cervical mucus).

So according to Persona tests, the best time to start having intercourse is when estrogen begins to grow and therefore the left line begins to become less marked.

When to start ovulation tests?

This depends on how long the menstrual cycle lasts, i.e. how many days pass from the first day of flow to the day before the next period.

In order not to start running them too early and therefore to avoid wasting tests unnecessarily, a few easy calculations are enough (which are based on the advice of the Clearblue site)

Start counting on the first day of your period

With a 20-day cycle, it’s enough to start testing on day 5
With a 21 day cycle it is enough to start testing on the 5th day
With a 22 day cycle it is enough to start testing on the 5th day
With a 23 day cycle it is enough to start testing on the 6th day
With a 24 day cycle it is enough to start testing on the 7th day
With a 25 day cycle it is enough to start testing on the 8th day
With a 26 day cycle that is enough to start testing on the 9th day
With a 27 day cycle that is enough to start testing on day 10
With a 28 day cycle that is enough to start testing on the 11th day
With a 29-day cycle, that’s enough to start testing on day 12
With a 30 day cycle it is enough to start testing on the 13th day
With a 31-day cycle, that’s enough to start testing on day 14
With a 32 day cycle it is enough to start testing on the 15th day
With a 33-day cycle, that’s enough to start testing on day 16
With a 34-day cycle, that’s enough to start testing on day 17
With a 35-day cycle, that’s enough to start testing on day 18
With a 36-day cycle, that’s enough to start testing on day 19
With a 37-day cycle, that’s enough to start testing on day 20
With a 38-day cycle, that’s enough to start testing on day 21
With a 39-day cycle, that’s enough to start testing on day 22
With a 40-day cycle, that’s enough to start testing on day 23
With a 41-day cycle, that’s enough to start testing on day 24
With a 42-day cycle, that’s enough to start testing on day 25
With a 43-day cycle, that’s enough to start testing on day 26
With a 44-day cycle, that’s enough to start testing on day 27
With a 45-day cycle, that’s enough to start testing on day 28

Clearly, those with an irregular cycle will need to use ovulation tests for a wider range.

Ovulation tests: when they are useful and when not

Ovulation tests can be considered a tool that adds to the calculation of the fertile period (for those who have regular cycles) or to the monitoring of the basal temperature and / or the analysis of the cervical mucus . In fact, they can become very useful if the basal temperature graph is difficult to interpret.

If, on the other hand, the cycles are very long or irregular, using the sticks could be quite expensive and above all useless if you suffer from PCOS (polycystic ovary syndrome).

This condition is characterized by hormonal imbalances that lead to higher LH levels: as a result, tests can come back positive even far from ovulation .

In conclusion

Whether you are regular or not, without making many calculations, you should start doing ovulation tests when fertile mucus begins to appear . You can also help yourself with the basal body temperature measurement.

Knowing your body inside out will make it much easier to understand when ovulation occurs and therefore also to conceive a child.

Dr. Kathryn Barlow

Kathryn Barlow is an OB/GYN doctor, which is the medical specialty that deals with the care of women's reproductive health, including pregnancy and childbirth.

Obstetricians provide care to women during pregnancy, labor, and delivery, while gynecologists focus on the health of the female reproductive system, including the ovaries, uterus, vagina, and breasts. OB/GYN doctors are trained to provide medical and surgical care for a wide range of conditions related to women's reproductive health.

Ovulation tests: what they are, how they work and when to start doing them