Many women don’t know, but the ovulation test can show a positive result before the menstrual period. Are you one of these women? The ovulation test is a great ally for women who want to get pregnant, and a positive result close to when your period should start can be exciting news regarding pregnancy. However, some aspects should be considered before taking an ovulation test before your period is late or even after it is already late.

What Is an Ovulation Test?

The ovulation test1 is a paper strip produced by expert manufacturers in home diagnostics, which will determine through a test line (which contains antibodies) if and how much of a certain hormone is present in the body at the time of testing. This test contains antibodies that capture hormonal levels in urine or even in blood plasma, as in pregnancy tests. The ovulation test strip is very similar to the HCG test, and it can detect fertility-related hormones. Therefore, the ovulation test should be used mainly around the time of ovulation to determine the exact day, the most fertile day of the cycle.

When Should You Do the Ovulation Test?

The ovulation test is usually performed close to the fertile window, which can be determined by the duration of your menstrual cycle. To count the days of your menstrual cycle, you need to count the first day of bright red bleeding for two months. The total number of days between them is your cycle length. For example: if you start your period on August 10 and again on September 14, your cycle is 34 days — the interval between one period and the next. You can easily calculate your fertile window here in the ovulation calculator.

When Is the Ovulation Test Considered Positive?

Unlike pregnancy tests, ovulation tests can show a second line every time they are performed. It’s not a rule, but it happens frequently. What determines that the test is positive for ovulation and that the woman will be fertile within a few hours (12 to 48, depending on the intensity of the results line) is the color of the test line. When it is as dark as the control line or even darker, ovulation will probably happen soon. Remember that the egg stays available for fertilization in the fallopian tube for up to 24 hours, so the woman should have intercourse as soon as the test is positive and keep testing until the line becomes faint again.

Positive Ovulation Test Before Menstruation

The concentration of LH (luteinizing hormone) in the body peaks considerably near the fertile period — this is what makes the dominant follicle, the one prepared to rupture, be released during ovulation. We know that this peak is what determines the test is positive, but there is a situation where the test also turns positive, even when you’re not in your fertile phase, but at a time close to when your period should come. There are two explanations for this:

  1. If you are tracking your fertility and take the ovulation test during the ovulation window, and you can see the test line progress from faint to its maximum peak, dark and then fade again, you have certainly ovulated. When you repeat the test close to your period and it turns positive again, with the intensity typical of ovulation or very close to it, there is a chance you have HCG in your body, which means you could be pregnant2. This can happen because the structures of LH and HCG, the hormone exclusive to pregnancy, are very similar. You could say they’re almost identical twins, and so, the antibody in the ovulation test could be “fooled” by HCG. It’s almost confusing, but very plausible.
  2. The second possibility for a positive ovulation test before your period is actually ovulation occurring later than expected. If you take the test and can’t see the LH peak on the strip, it could be that your hormones took a little longer to prepare for ovulation this cycle. This is called late ovulation and is much more common than you might think, especially for women with irregular cycles. To reach this conclusion, you need to look out for signs of ovulation3:
  • Abdominal pain on one or both sides
  • Elastic cervical mucus or a lot of vaginal moisture
  • Increased libido
  • Breast tenderness

The important thing to remember is that not every positive ovulation test before menstruation is related to pregnancy. To confirm a pregnancy, you need to do specific HCG tests. It is recommended to take a pregnancy test, which is appropriate for the pregnancy hormone, as soon as your period is late. If this is not enough, take a quantitative beta HCG test.Also see: Ovulation Test – How to Do and Interpret?Photos: Sapp