The menstrual cycle and the changes in basal body temperature and vaginal discharges
The proliferative phase (follicular phase)
During this phase, a primary follicle begins to grow in the ovary, induced by a follicle-stimulating hormone secreted from the pituitary gland. As the follicle matures and estrogen is secreted, the uterine lining starts to gradually thicken.
The ovum bursts out of its follicle when the levels of the follicle-stimulating hormone (FSH) and the luteinizing hormone (LH) reach their peak, stimulating the matured follicle. This is referred to as ovulation. Some women experience lower abdominal pain at this time.
The secretory phase (luteal phase)
Following ovulation, the follicle develops into a corpus luteum which secretes progesterone. This induces the uterine lining to further thicken and form a cushion, preparing the endometrium for a fertilized egg to be implanted in it.
The menstrual phase
During the menstrual phase, pregnancy occurs when an ovulated egg is fertilized by a sperm and implants itself in the lining of the uterus. However, the corpus luteum shrinks into a corpus albicans if pregnancy does not occur, causing estrogen and progesterone levels to drop. The uterus will then shed its unused lining and expel it along with blood. This process is referred to as menstruation.
What is basal body temperature?
The temperature of your body at rest
Basal body temperature is the temperature of a person’s body while expending minimum energy, or the temperature of one’s body at rest. It usually refers to the temperature taken immediately after waking up in the morning while still at rest.
A woman’s body shows minute changes in temperature
Women’s bodies, when going through ovulation and menstruation, show minute and periodical changes in temperature under the influence of female hormones. As such, we are able to recognize the changes in our body and in hormone levels by taking our basal body temperature daily.
How to take your basal body temperature
Use the basal body temperature thermometer
Make sure you use the basal body temperature thermometer to take your basal body temperature. While women experience both higher and lower temperatures periodically, the difference between the two phases is only 0.3 to 0.5 degrees Celsius at most. A regular thermometer will not register such a difference. Basal thermometers are available from pharmacies. You can use either glass or digital thermometers.
Take your temperature immediately after waking up while still lying down
When you wake up in the morning, put a basal thermometer in your mouth while you are still in bed, as getting up out of bed will raise your temperature. Place the thermometer under your tongue to hold it in place when taking your temperature.
Don’t forget to chart your temperature
A basal body temperature chart is a graph that shows the fluctuations of your basal body temperature. Don’t forget to chart your temperature in the graph, because the point is to identify the cycles between your lower temperature phase and your higher temperature phase. Basal body temperature charts are available at pharmacies. You can also download one here.
Make a note on your chart of any differences in the conditions under which you take your temperature
In principle, you should take your basal body temperature at the same time and under the same conditions every day. However you can’t be expected to stick to this all the time. Being too strict on yourself will also make it difficult for you to keep up with a routine. Just make a note on your chart whenever you are diverted from your routine, such as if you go to the bathroom immediately after waking up or if you overslept.
It also helps in looking over your chart to make a note about anything else that you may have noticed, such as when you had menstruation, vaginal discharges, spots, stomach aches, sexual intercourse, a cold, a drink, or little sleep.
If you miss a day, leave it blank, skipping the entry on the graph for that day.