If I had a nickel for every time someone asked me “how do I calculate my ovulation?”….well I would be on a beach vacation right now. So how do you know when you ovulate? Spoiler alert, it’s not your phone app!

Why Your Phone App Is Not The Answer

Although cycle tracking apps are great for tracking your menstrual cycle, they are just guessing when it comes to ovulation. Let’s say you have a 28-day cycle, the app is going to assume you ovulate around day 14. In reality, you could be ovulating as early as day 10. Since eggs only last for ~24 hours once they are released, there is a chance you are missing your ovulation window every month. On the flip side, you could be someone who ovulates later in your cycle, meaning you are having timed intercourse way too early. Although sperm can technically live inside the uterus and fallopian tubes for up to 3-5 days, many factors can shorten their lifespan. If you are someone who is trying to conceive, this can make matters very difficult. Since you only get one chance per month, we want to be as precise as possible with your ovulation and timing intercourse. 

What can I use to pinpoint my ovulation? 

Basal Body Temperature (BBT)

Your BBT can help confirm, not predict, ovulation; your BBT will rise after ovulation due to an increase in the hormone progesterone. If you consistently record your BBT for a few months, you will be able to determine when and if you have previously ovulated. Keep in mind that you are most fertile before ovulation; once your temperature rises conception is unlikely to occur. That’s why I recommend taking your BBT for a few months before you start trying to conceive. For example, if you find that your BBT consistently rises on day 16 of your cycle, you are likely ovulating on days 14-15 every month.

Ovulation Predictor Kits (OPK)

Ovulation predictor kits are also known as LH strips. They are commonly used to help women track when ovulation is about to occur. In general, they are more accurate than tracking your basal body temperature; one study found that LH strips were 97 percent effective at detecting ovulation, compared to 74 percent accuracy for BBT.  Once you have positive OPK, most women will ovulate within approximately 24-36 hours, although this can range from 16 to 48 hours depending on the individual. Depending on the kit, a positive OPK means a static smiling face or a line that is darker than the control line. Conceptions rates are highest on your peak day and the following day. Keep in mind these strips help predict but do not confirm ovulation, we will need blood work and ultrasound for that. It’s another reason why I recommend using a combination of several signs and symptoms to determine when you ovulate. 

***Keep in mind that false positives are much more likely to occur in women with PCOS. LH levels are chronically elevated as the body tries to ovulate. This can make timing ovulation much more difficult. For more information on this subject, be sure to pick up a copy of my book. 

Cervical Mucus

Cervical mucus is stimulated by estrogen, which rises during the first half of your menstrual cycle. High levels of estrogen cause an LH surge, which subsequently triggers ovulation. The quantity and quality of your cervical mucus are constantly changing throughout your cycle. Fertile cervical mucus, also called spinnbarkeit mucus is much thinner and slippery in nature. This helps transport sperm through the female reproductive organs to facilitate fertilization.

  • After your menstrual period: Many women report dryness or scant mucus
  • As your ovulation date approaches: As you move toward your fertile window, you will start to notice an increase in mucus. It may appear creamy and white, similar to sunscreen. 
  • Peak fertility: One to two days before ovulation, mucus production will be at its highest due to rising estrogen. This is when many women report a stretchy, clear, egg white mucus that you could stretch between two fingers.  
  • After ovulation: Quantity will once again decrease becoming dry and scant. 

Preconception Care Matters

As you can see, calculating your ovulation is not so straight- forward! I recommend working with a Naturopathic Doctor when trying to conceive to understand your body and time intercourse appropriately. A preconception care plan can optimize your chances of conceiving every month and ensure you are not missing your fertile window.