Predicting Ovulation with Temperature Charting

Understanding your menstrual cycle and knowing your most fertile time can be really helpful if you’re planning a pregnancy.  Charting your basal body temperature and monitoring changes in your cervical mucous can assist in identifying when you’re ovulating, helping you get pregnant more quickly or identify potential fertility problems.  Best of all, it’s easy and cheap!

If you’re planning a pregnancy make sure you visit your GP for a pre-pregnancy check-up.

How does temperature charting work?

Basal body temperature (BBT) is your temperature when you first wake up in the morning.  Changes in the hormones controlling your menstrual cycle cause subtle differences in your BBT, and changes to the mucous produced by glands in the cervix.  Recording your BBT and cervical mucous over a period of a few months can give you an accurate indication of when you are ovulating.

How do I start?

  1.  Download a basal body temperature chart.  There are heaps on the internet, just make sure you get one with measurements in Celsius.  There are also sites and apps if you prefer to chart online or on your phone.  I like Fertility Friend.   I also have some printed copies in the clinic, collect one next time you visit!
  2. Buy an ovulation thermometer from your chemist.  There are mercury and digital ovulation thermometers, either is fine.
  3. Start on the first day of your next cycle (the first day of your period). Take your temperature at around the same time each morning, before getting out of bed each day.  There is no need to take a vaginal temperature reading, just pop the thermometer in your mouth.
  4. It’s best to try to chart as accurately as possible for the first few months so you can identify patterns in your cycle.  Ideally, you won’t eat, drink, or move around before you take your temperature.  Your temperature readings can also be affected by alcohol, having less than 3 hours sleep and some medications.
  5.  Monitor your cervical mucous.  You can do this by either looking at the toilet paper after you wipe, or inserting a clean middle finger into your vagina towards the cervix.

There are a number of things you may find:

– Menstrual blood

– Dry, cloudy, or creamy cervical mucous

creamy cervical mucous

creamy cervical mucous

stretchy or egg white cervical mucous

stretchy or egg white cervical mucous









– Cervical mucous that is thin, clear and slippery (often described as being like egg white).  You may be able to stretch the mucous between your fingers.  The body produces this mucous to facilitate the movement of sperm to the ovum.  Your most fertile time is when this mucous reaches its peak in volume and slipperiness.

You may also wish to record other physical changes such as breast tenderness, bloating, bowel changes or abdominal pain.  You can also record when you have sex.

When am I ovulating?

A typical chart will show consistently lower temperatures before ovulation, then consistently higher values after.  In the image below, the temperature rise from days 14-18 show that ovulation has occurred, probably on day 13.  After ovulation the temperature should remain high until the end of the cycle, when it will either continue to climb (pregnant) or drop (not pregnant).  Some women notice a dip in temperature on the day ovulation occurs – if you notice this pattern consistently over a few cycles, this is a good time to have intercourse.

You don’t need to have sex on the day of ovulation to fall pregnant; some couples like to try every second day around the expected time of ovulation.

A typical ovulation chart

A typical ovulation chart












You may occasionally get errant readings that don’t fit into the wider pattern.  If they don’t happen often you don’t need to worry, but if your cycle doesn’t fit the usual pattern after a few months of readings you should seek advice from a health professional.

Is temperature and mucous charting right for me?

Temperature charting is easy and a lot cheaper than using ovulation detection kits each month.   Most women find having an understanding of their menstrual cycles and fertility gives a sense of empowerment when trying to have a baby.   Just monitoring your cervical mucous on its own is a strong indicator of ovulation; you may prefer to try this on its own after a few months of temperature charting.

Some women find ovulation charting creates anxiety or stress around trying to conceive.  If this is you, you could try charting for just a few cycles to get an idea of what’s going on, and then just focus on your mucous changes when you get the hang of it.  It is also helpful to have a few months charted if you do experience fertility problems and want to try Chinese medicine; the charts can help your practitioner identify any imbalances in your body.

When to Seek Help

Chinese Medicine treatments can support and balance the body and are helpful for all women trying to get pregnant, but there are a few circumstances in which a course of treatment may be particularly helpful.

If you’ve been charting for a few months and yours doesn’t broadly match the typical one shown above, you may have an energetic imbalance which is affecting your fertility.  Acupuncture and Chinese herbal medicine can help to nourish your body and restore balance.

If you’ve been trying to fall pregnant for 6 months and nothing is happening, or 3 months if you’re over 40.  Healthy couples under 35 can take up to 1 year to fall pregnant, so don’t panic.  However, it’s worth seeking help sooner rather than later to identify any potential problems early.  Acupuncture and herbal medicine can help to support and optimize your fertility.