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Menstrual Calendar, Charting Your Signs of Fertility: Part 2

Menstrual Calendar, Charting Your Signs of Fertility: Part 2

In Part One of this series we went over cervical mucus and how to determine when we are ovulating. Today we are covering taking your basal body temperature to determine where you are in your cycle and if you have ovulated, otherwise referred to as fertility charting.

Article by: Marie Zenack

Basal Body Temperature

If you are not sure you are ovulating, you can take your temperature. The body’s resting temperature increases four-tenths of a degree Fahrenheit or two-tenths of a degree Centigrade under the influence of progesterone at ovulation. Observing this sign involves taking your temperature at the same time each morning before rising. (This is not as hard as it sounds. It takes less than two minutes and you can go back to sleep if you want.)

To observe your temperature rise, buy a BD brand or ibasal digital basal thermometer. This brand will give you a consistent and accurate reading. Other high-quality brands of digital basal thermometers are also probably accurate, but have not been tested for fertility awareness. Make sure the battery is good. (You can replace it.) An ordinary clinical thermometer is not accurate enough for fertility awareness, nor is the “ear thermometer” (tympanic thermometer).

Take your temperature every day immediately upon waking, before 7:30 a.m. The body’s rhythms (circadian rhythms) fluctuate over a 24-hour period. Your temperature is lowest in the early morning and highest in the afternoon. Fluctuations are greater after 7:30 a.m. If you go to bed before midnight and wake up before 7:30 a.m., you will get the clearest temperature readings.

If it is not convenient to take your temperature immediately upon waking, you may take it during light morning activity. For example, if you need to go to the bathroom, you may take your temperature while getting up and using the toilet. But be consistent about the circumstances under which you take your temperature. If you take it during light morning activity, take it that way every morning. Don’t take it sometimes before getting up and at other times during light morning activity. If you have sexual relations, take your temperature before.

Many women find that the digital thermometers require such a short time to use that it is easy to take their temperature before getting up. Take your temperature by mouth. Under arm and ear temperatures are not accurate enough for family planning purposes. The thermometer will beep softly several times before beginning to beep slightly louder and repeatedly. Keep the thermometer under your tongue until the louder, repeated beeps begin. You can read and chart your temperature when it is convenient. Your thermometer has a recall button that allows you to read the last temperature taken. Be sure to wash your thermometer after each use.

To download a free fertility chart click here…

Complete Series
Part 1: Cervical Mucous
Part 2: Basal Body Temperature
Part 3: Charting

About The Author

Marie Zenack is a teacher of fertility awareness and a facilitator of women’s rites of passage at Earth Wisdom, Natural Family Planning and Fertility Awareness.

Dr. Christine Traxler M.D., OB/GYN
Dr. Christine Traxler M.D., OB/GYN

Dr. Traxler is a University-trained obstetrician/gynecologist, working with patients in Minnesota for over 20 years. She is a professional medical writer; having authored multiple books on pregnancy and childbirth; textbooks and coursework for medical students and other healthcare providers; and has written over 1000 articles on medical, health, and wellness topics.  Dr. Traxler attended the University of Minnesota College of Biological Sciences and University of Minnesota Medical School,  earning a degree in biochemistry with summa cum laude honors in 1981,  and receiving her Medical Doctorate degree (MD) in 1986.

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    Thank you for your amazing website! I have a question- I am trying to chart my basal temperature but feel that my wake up time is not very consistent. I often get woken up by my cat as early as 5am and use the bathroom then go back to sleep till about 7:30am-8am. Is it best to take my temperature at 5am when he wakes me up or after I wake up the second time? This pattern is not consistent, which is one reason it’s confusing. I have not been successful at charting my temperature because of this. Thankfully my cycle is pretty regular, and I can tell a lot by my cervical fluid, but I would like to see if there is a dip in progesterone in the second half of cycle… Thanks for your help!

    • Dear Sylvia,

      It would be better to take your basal body temperature at the earlier wake-up time, before you rise (or as you rise) and go to the bathroom. This might help make charting a bit easier.

  2. Update 2014 – We are back! We have been away for a while and we sure have missed all of your wonderful questions and thoughts on our articles. Moving forward, one of our staff herbalists will be here to respond to comments! We look forward to connecting with our readers once again!

  3. well I didn’t plan to have unprotected sex on the days of ovulation which was June 3/4/5 and each time he ejaculated inside me, I was wet and he noticed but it didn’t stop him from enjoying the feeling and i’m just waiting for my next period to come witch is on June 18th 2012. and every since those days and up until June 12 I’ve been experiencing : mild cramps in the abdomen, and in my lower back, i’ve been feeling nausea, slight diarrhea, itchy breasts, tiredness, and feeling like i have a fever off and on it comes and goes, urinating more often, and slight discharge feeling wet. are these signs of early pregnancy? I took a pregnancy tests on June 10th and it came back neg, could I have taken it to soon?