Why Chart? 

Charting your menstrual cycle is a low cost, relatively easy way to track your fertile window and help time intimacy more accurately. It can help detect obstacles to conception, such as late ovulation or anovulation (where the egg was released from the ovary later than expected, or not at all), infertile cervical fluid, and miscarriage occurrences. It can also clue us into potential hormonal imbalances such as low progesterone and hypothyroidism, all conditions that your Naturopathic Physician can help with.

There are a couple of pieces of charting that together give us a good picture of what’s going on – BBT, cervical fluid changes and other fertile signs. In this post we’ll focus on BBT.

Oral Basal Body Temperature (BBT)

This is your temperature taken right when you wake up in the morning. To be accurate it needs to be taken at the same time every day before you get up out of bed and move around.

You’ll need a BBT thermometer, which covers the normal range of temperature (not the fever range) and is more sensitive than a typical thermometer. This is important because the temperature change we’re looking for can be as small as 0.2 of a degree! You can record your temps on an app or temping chart paper like this one. 

What it tells us:

Typically, body temp is pretty consistent before ovulation and spikes after ovulation. This is because progesterone, which increases after ovulation, causes an increase in temperature. Charting can tell us:

-      whether ovulation occurred ( having a bleed every month doesn't mean an egg was released that cycle)

-      when it occurred 

-      if there’s a short luteal phase that’s not allowing enough time for a fertilized egg to implant (the luteal phase is the second half of the cycle from ovulation to the period)

-      if someone’s pregnant 

-      the predicted due date 

-      whether ‘infertility’ is really recurrent miscarriage

Charting temps for a few months is ideal to see whether cycles and ovulation are consistent, and if there are any irregularities that might need to be addressed to improve fertility. Temping is so informative, but although it confirms that ovulation occurred, by that point the fertile window has already passed, and temp charts are not predictive of when ovulation will occur in the next cycle. Using fertile signs that we’ll talk about in part two with temping is the best way to determine your fertile window.