Hormonal changes associated with ovulation produce a slight rise in a woman's basal body temperature, approximately 0.3°C, as well as other recognizable signs such as changes in cervical mucus. Learning to record and interpret basal temperature changes is known as the Basal Body Temperature Method (BBT). By monitoring the basal temperature changes, couples, in conjunction with their physician or family planning counselor, may be able to determine that ovulation has taken place and approximately when. Monitoring other symptoms, such as cervical mucus changes, can assist in determining the fertile days prior to ovulation. When temperature changes are used in conjunction with other fertility symptoms, such as the cervical mucus, it is known as the Sympto-Thermal Method. Time of ovulation can be used to time sexual intercourse during fertile days to aid in increasing the likelihood of achieving pregnancy.
THE FEMALE REPRODUCTIVE CYCLE
In order to understand the instructions which follow, it is helpful to review some basic points of human female reproductive activity:
A. Hormones are secreted to prepare for ovulation
At the beginning of each menstrual cycle, the pituitary gland secretes a hormone, FSH (follicle stimulating hormone), that acts upon the ovaries to prepare for ovulation. As one or more follicles in an ovary prepare for ovulation, they secrete another hormone, estrogen, that prepares the uterus for pregnancy by causing the inner lining of the uterus, the endometrium, to build up. The estrogen also causes some glands or crypts in the cervix to secrete a mucus discharge that is necessary for fertility. This mucus changes the environment in the vagina to make it more favorable to sperm life and likewise provides a medium through which the sperm swim upward into the uterus. The mucus typically starts as a rather sticky substance. Then, during the time of fertility, it becomes more fluid and copious, usually attaining a consistency very similar to raw egg white. Sometimes the mucus becomes so watery that it will no longer stretch like raw egg white but continues to produce sensations of lubrication or wetness at the outer lips of the vagina.
At ovulation, the ovarian follicle releases an ovum (egg) which is picked up by one of the Fallopian tubes near the ovary and transported toward the uterus. In order for pregnancy to occur, the egg must be fertilized in the Fallopian tube by sperm within 24 hours offer ovulation, because after that time the egg disintegrates and cannot be fertilized.
C. Post Ovulation
After ovulation, the ovarian follicle that released the egg secretes another hormone, progesterone, which suppresses further ovulation in that cycle. The progesterone continues to build the endometrium and maintains it after ovulation. It also causes the basal temperature to rise and the cervical mucus to thicken so much that it appears to dry up. When it stops, the inner lining of the uterus can no longer be maintained, so it is sloughed off in the process called menstruation, and the menstrual cycle starts again.
TIMING OF OVULATION
By carefully taking the basal temperature first thing upon waking and recording it on a chart, the characteristic rise in temperature after ovulation can be observed. The OVUTEMP™ Ovulation Thermometer is extended between each tenth of a degree, making it easy to read and record the slight temperature variations that occur when ovulation has taken place. The Ovulation Thermometer may be used as an oral, rectal or vaginal thermometer. However, since body temperature will vary with each site, you should choose one method and stick to it, using the same thermometer.
RECORDING THE BASAL TEMPERATURE
Refer now to the blank chart provided.
First, prepare your chart following these instructions. Day 1 for each cycle is the first day of menstruation, above the preprinted days of the cycle enter corresponding calendar dates. During the menstrual flow, it is not necessary to record your temperature (unless you have short cycles). Instead mark an X or other code in each space provided to indicate the number of days your period lasts. Begin recording your basal temperature the first morning following the end of menstruation. The basal temperature should be taken every day at the same waking time until the beeper sounds. Detailed instructions are in the next section, "How To Take Your Basal Temperature." Record the temperature on your chart. For each daily temperature, trace down the column below the cycle day until it intersects with your recorded temperature. Place a dot at the intersection. The numbers on the chart represent two hundredths of a degree on the thermometer scale. A notation should be made for any rise in temperature presumably due to illness, emotional upset or a sleepless night. Intercourse can be indicated by placing a circle or other code around the dot of the appropriate day. Keep a charted record for at least three months in order to be sure that you have determined your approximate time of ovulation during any regular menstrual cycle. Careful temperature recording will help establish your particular pattern. You may want to make copies of the blank chart enclosed for this purpose. Completed charts can then be presented to your physician or family planning counselor, who will assist you In accurately interpreting results.
HOW TO TAKE YOUR BASAL TEMP
1. Insure the digital probe is clean by wiping it with alcohol or warm soapy water (not hot).
2. Take the temperature
The basal temperature should be taken at the same waking time each morning. Since any activity may tend to raise the temperature, postpone going to the bathroom, eating, smoking or drinking. Cold drinks lower mouth temperature; hot drinks, smoking and exercising cause higher readings. Electric blankets can definitely affect the basal temperature. Therefore, if one is used, it should be kept at the same setting throughout the cycle or at least until well into the time of post ovulation infertility. Having made sure that the thermometer probe is clean, insert the probe in the mouth (under the tongue), rectum or vagina. In the rectal or vaginal method, the probe should be inserted approximately 3/4 of the probe's length. CAUTION: Since the temperature of various parts of the body varies, it is important you select one method of use and stay with it during the period of comparison.
For oral use: Place well back under the tongue, close the lips and keep them closed until the beeper sounds and the thermometer is withdrawn.
For Rectal use: Coat the probe lightly with lubricant and insert approximately 3/4 of the length into the rectum and wait for the beep to sound before withdrawal.
For Vaginal use: No lubricant is necessary. Follow the same procedure as stated above for rectal use.
*Basal temperature is the normal body temperature of a healthy person immediately upon awakening after a restful night's sleep. More precisely, it is the body temperature as measured under so called basal conditions (12 hours after eating, after a restful sleep, no exercise, no emotional excitement, normal ambient temperature).
*Note: Some women find that very mild activity for a few minutes does not affect the temp when taking oral temperatures; they can go to the bathroom and/or get dressed without effect on basal temperature. You can determine your sensitivity by comparing the five temperatures with one taken immediately afterwards while up and around. Make such comparisons for at least a week. If you have any doubts, avoid activity until your temperature taking is complete.
3. Read the thermometer
After the "beep" has sounded, withdraw the thermometer, read the temperature from the LED digital display and record the temperature on the chart in the appropriate place.
NATURAL FAMILY PLANNING
In natural family planning, there are several ways of determining the end of pre-ovulation fertility and several guidelines for determining the beginning of Post-ovulation infertility. In the experience of those teaching natural family Planning, most unplanned pregnancies occur because of improper guidelines for determining the beginning of post-ovulation infertility. This brochure does not include guidelines for natural family planning, since it is beyond the scope of these instructions. Your digital thermometer only helps you determine when ovulation has occurred. Calculating infertile periods involves other bodily signs in addition to temperature changes and requires professional guidance when avoidance of pregnancy is your objective.
1. Temperature Ranges
The basal temperature before ovulation is usually in a range between 35.8°C and 36.7°C. Probably the most frequent range is between 36.3°C and 36.5°C. After ovulation the basal temperature rises about 0.3°C and stays in that higher range until the beginning of the next menstrual period. The highest probability of conception is during the days immediately prior to ovulation as well as on the day of ovulation itself.
2. Other Observations
Remember that the thermometer is designed only to help determine when ovulation has occurred. Mucus observations, as noted in "The Female Reproductive Cycle," can also be helpful when recorded as shown on the chart. Notation of these changes, in addition to your temperature pattern, will assist your physician or counselor in providing you with proper guidance. It is commonly suggested that couples who have had difficulty in achieving pregnancy should not have coitus more than once a day or on consecutive days, in order to maintain satisfactory quantities of sperm. The most fertile time continues up through the first day of drying up of the mucus or the first day of temperature elevation, whichever comes later. The temperature record should be maintained on a daily basis. If pregnancy is achieved, the basal temperature will remain elevated for several months. A temperature pattern that remains elevated for 21 days (or a week more than your usual elevated pattern) is a good indicator that pregnancy has been achieved. If pregnancy has not been achieved with six cycles, your physician or counselor will guide you accordingly,
It should be clearly understood that the effectiveness of the methods outlined for seeking and avoiding pregnancy depend on such factors as a woman's individual reactions, the accuracy with which daily temperatures and other symptoms are recorded, and the absence of outside factors which may affect body temperature. Consequently, no representation of any kind can be made by the manufacturer as to the reliability of the results obtained in any individual case, and the patient is urged to consult with and be guided by the advice of her physician or counselor in the use of the Digital Basal Thermometer.
BBT CHARTING BASICS
Top of the Chart: To fill in the information at the top of the chart, simply fill in your name; the current month or months for this cycle; the year; the shortest cycle you've had in the past year; the longest cycle of the past year; and when you get your period, put in the length of this cycle. The length will usually be one day shorter than the number of columns you have filled out on this chart (the last day should be the day your menses start). Be sure to repeat the last temperature as your start day on the next chart.
Cycle Day: your cycle begins on the first day bleeding begins and ends the day before your next period. The "average" woman has a 28-day cycle, but many women have shorter or longer cycles. This chart will work for anyone with cycles up to 30 days. The cycle day is listed in two places to make it easier to read your chart.
Intercourse: Mark the dates on which you have intercourse with an A for morning and P for afternoon/evening (simply use an X if you don't want to be that specific).
Time Temp Taken: For the best results, you should take your temperature at as close to the same time each day as possible. Sleeping an hour late, for example, could account for as much as 0.1ºC rise in your waking temperature.
Waking Temperature: Simply record the number that corresponds with your temperature. Note that your temperature should shift 0.2 - 0.6 degrees Celsius after you ovulate and should stay elevated for 12-14 days. It is common to have a dramatic temperature drop the day your period begins. If your temperature stays up for 18 days without dropping, you should probably test for pregnancy.
Cervical Fluid: What you want to do here is note the consistency of your cervical mucus. See suggested codes above.
Vaginal Sensation: Enter in a one word description for the overall feeling you've had throughout the day. Examples include, dry, moist, sticky, and wet.
Cervix: There are two lines here. The top one is for cervical opening. Use a period C for closed, an M for partly open (middle), and an O for open. The second line is for listing firm (F), medium (M) or soft (S) or, if your prefer, high (H), middle (M) or low (L).
Cervical Fluid Description: What you want to do here is note description of your cervical mucus. See suggested codes above.
LH Surge: The information for this line will require buying an ovulation predictor kit such as our Ovulation Prediction Tests or having your LH (luteinizing hormone) measured by your physician. Note an N on days where you've gotten a negative result, and put and P on the day you detect the surge.
Ovarian Pain: If you experience any ovulation pain or cramping, note that here with an L for left and an R for right to specify the side on which you felt pain, or M for middle.
Miscellaneous: This is just as the name implies: a place to put down notes about anything that you think may be relevant. Did you forget to take your temperature? Did you wake up not feeling well? Restless night? If you don't have room make up your own legend codes.
Cramps, Bloated, Headaches, Sore Breasts and Emotional: Simply mark an X in the boxes that apply to you on a given cycle day.
Ovutemp Ovulation Thermometer Instructions
Views 20 Likes Comments Comment
2 April 2009
Have something to share, create your own Guide... Write a Guide
Explore more Guides