What is the basal temperature chart for ovulation? Measurement of basal temperature during ovulation

Ovulation is a process that takes place in the body of a healthy woman, which is associated with the release of the ovule into the uterine tube for further fertilization. Knowing the day of the onset of ovulation can help plan a pregnancy or prevent an unwanted conception. There are several methods for determining it, but the most accessible and simple is measuring the basal body temperature.

What is it?

Basal body temperature (BTT) is an indicator that is measured in a state of complete rest, in the anus, immediately after a morning awakening. It is a reflection of the hormonal background of a woman and helps to identify problems in the work of the sex glands. However, more often BTT is used to determine days that are favorable for conception.

Many gynecologists advise women to maintain their basal temperature schedule. Especially for those who plan to replenish the family. The basal temperature chart for ovulation has its own characteristics. It allows you to calculate the most suitable day in order to become pregnant. Basal temperature directly depends on the hormonal processes in the body of a woman.

Menstrual cycle and its phases

The female organism is created for the continuation of the genus, therefore all the processes taking place in it are aimed at providing conception and preparing the organism for pregnancy and childbirth. The menstrual cycle represents three consecutive phases: follicular, ovulatory and luteal.

The first phase begins with menstrual bleeding, followed by the formation of the follicle in the ovary and the formation of a new endometrium. Its duration may suggest a graph of basal temperature. Its normal duration is 1-3 weeks. In this phase, the role of phyllikulostimulating hormone and estrogen. It ends with the maturation of the follicle.

The second phase is directly ovulation. The walls of the follicle burst, and the egg passes through the fallopian tube towards the spermatozoon. The phase lasts about 2 days. If fertilization occurs, then the embryo attaches to the endometrium, if not, the egg dies. On a normal chart, the basal temperature on the day of ovulation is at the lowest level for the entire cycle.

In the third phase, the development of progesterone begins. It is produced by the yellow body that formed on the site of the ruptured follicle. Basal temperature after ovulation changes in the big party - on 0,4-0,6 ° С. During this period, the female body is preparing for bearing and preserving the fetus. If conception does not occur, then the concentration of female sex hormones decreases, and the circle closes, the follicular phase begins. Its duration is normal for all women is about 2 weeks.

Why do temperature fluctuations occur?

The measurement of basal temperature in ovulation as a method that characterizes the hormonal changes in a woman's body was proposed in 1953 by the scientist Marshall. And now WHO is approved as the official way to identify fertility. Its basis is a regular change in the concentration of progesterone in the blood. This hormone acts on the thermoregulatory center in the brain, which causes a local increase in temperature in the organs and tissues of the small pelvis. That is why a sharp increase in temperature in the anal region occurs in the luteal phase.

Thus, ovulation divides the menstrual cycle into two parts: in the first, the average temperature is approximately 36.6-36.8 ° C. Then it goes down by 0.2-0.3 ° C for 2 days, and then rises to 37-37.3 degrees and at this level holds almost to the end of the cycle. A normal basal temperature chart for ovulation is called biphasic.

The measurement of BTT can help to determine with high accuracy a day that is successful for conception. According to statistics, it is known that the highest probability of getting pregnant will fall on the day before and after the temperature increase - 30% each. 2 days before the jump - 21%, 2 days after - 15%. Pregnancy can occur with a 2% probability if fertilization occurs 3 or 4 days before the temperature rises.

What is this method used for?

If you make a constant graph of basal temperature, the norm and pathology begins to be traced in 2-3 cycles. The curves obtained can answer many questions. Therefore, gynecologists strongly recommend this method for solving the following problems:

• Determination of auspicious day for conception.
• Early diagnosis of pregnancy.
• As a method of contraception.
• Identification of malfunctions in the sexual glands.

Basically, basal temperature is measured to calculate the day of onset of the ovulatory phase of the cycle. This is the easiest and cheapest way. Determine ovulation at basal temperature is very easy, if you regularly take measurements and observe all the rules.

The right measurement is the guarantee of the effectiveness of the method

In order for the results of the method to be true, it is necessary to follow all instructions when measuring the BTT, since it is very important that the basal temperature chart for ovulation includes only accurate and reliable data. There is a set of basic rules:

• The temperature is measured daily at the same time (optimal - 7.00-7.30) in the rectum.
• Before the procedure must sleep at least 3 hours.
• If a woman needed to get out of bed before the time of measurement, then the readings should be removed before taking a vertical position.
• The thermometer must be prepared and placed near the bed. Shake him better before going to bed.
• The temperature can only be measured in a horizontal position, lying motionless on its side.
• During the cycle, you can not change the thermometer.
• It is better to enter the testimony in the graph immediately after the measurement.

For measurements, both digital and mercury thermometers are suitable. But the infrared thermometer for this method is absolutely not intended, because it is more likely that there is an error in the results. Since the basal temperature before ovulation and on the day of its onset differ only by 0.2-0.3 ° C, such a thermometer may not show this difference. Electronic thermometer gives large errors, if not follow the instructions for its use. The most accurate indicators can be obtained using a mercury thermometer, but it requires special care when handling.

When the received indicators can be incorrect

It should be remembered that the basal temperature for ovulation, the rate of which for each woman is individual, can fluctuate depending on the influence of different factors. Often, external influences on the body lead to the fact that the indicators of BTT are highly distorted and have no informative value. Such factors include:

• Hops, crossings, business trips.
• Stress.
• Excessive intake of alcohol.
• Reception of psychotropic and hormonal preparations.
• Inflammatory processes in the body, fever.
• Increased physical activity.
• A short sleep.
• Non-observance of the measurement instructions.
• Sexual intercourse a few hours before the measurement.

If something happens from the above list, then you should not trust the measurements. And the day in which there was a violation, you can not take into account in the construction of the schedule.

How to build a basal temperature chart

To build a basal temperature chart, you need to take measurements every day and make entries in a specially marked exercise book. The graph represents the intersection of two lines at a right angle. The vertical axis contains temperature data, for example, from 35.7 to 37.3 ° C, and the menstrual cycle days are on the horizontal axis. Each cell corresponds to 0.1 ° C and 1 day. Having made the measurement, it is necessary to find the cycle day on the graph, hold the line mentally upward and put the point opposite the desired temperature. At the end of the cycle, all points of the graph are joined, the resulting curve is an objective representation of hormonal changes in the female body.

In the graph it is necessary to indicate the current date and to construct a graph for special notices. In order for the data to be complete enough, you can describe your state of health, symptoms or situations that might appear on the basal temperature change.

If a woman is not very clear how to draw up a basal temperature schedule, the gynecologist from the women's consultation will definitely explain how to do this, and also help decipher the obtained data.

Now there are many programs with which you can create an electronic schedule, which will always be at hand. In this case, a woman simply needs to enter temperature indicators. The rest will be done by the program.

Decoding the schedule

In this method of determining fertility, it is important not only to construct, but also to decipher the graphs of basal temperature. The norm for each woman is individual. However, there is an approximate view of the schedule, which should be obtained if the sex glands are working properly. To analyze the resulting curve, the following elements should be constructed: the overlapping line, the ovulation line, the duration of the second phase.

The overlapping (middle) line is built on top of 6 points of the follicular cycle, without taking into account the first 5 days and days, when the indicators were strongly deflected due to the influence of external factors. This element has no semantic meaning. But it is necessary for clarity.

Basal temperature on the day of ovulation is reduced, so to determine the day for successful conception, you need to find consecutive points that are under the overlapping line. In this case, the temperature values of 2 out of 3 points should differ not less than 0.1 ° C from the midline, and at least 1 of them should have a difference of 0.2 ° C with it. The next day after this, you can observe the jump of the point upwards by 0.3-0.4 degrees. In this place, and you need to build a line of ovulation. If there are difficulties with this method, then you can use the "finger" rule to plot the graph. To do this, it is necessary to exclude all points that differ by 0.2 degrees from the previous or subsequent indicator. And based on the received schedule to build a line of ovulation.

The basal temperature after ovulation in the anus should be kept at a level above 37 ° C for 2 weeks. Variations in the duration of the second phase or a small temperature jump indicate abnormalities in ovarian function or low productivity of the yellow body. If 2 cycles in a row duration of the second phase does not exceed 10 days, then it is necessary to consult a gynecologist, as this is the main sign of progesterone insufficiency of the luteal phase.

The basal temperature chart for ovulation should also correspond to the norm for such a parameter as the temperature difference between the follicular and luteal phases. This figure should be equal to more than 0.4 ° C.

What does the graph look like in the presence of ovulation and in pathologies

A normal ovulatory chart consists of two phases. In the first one, one can observe an average temperature of 36.5-36.8 ° C for 1-3 weeks, then fall by 0.2-0.3 ° C and a sharp rise to 37 ° C and higher. The second part of the schedule should not be shorter than 12-16 days, and before the onset of bleeding there is a slight decrease in temperature. Graphically it looks like this:

Also, examples of basal temperature charts should be given, in which pathology can be traced. The curve in this case will differ from the norm according to various characteristics. If there is estrogen-progesterone insufficiency, then the temperature jump will be no more than 0.2-0.3 ° C. This condition is fraught with infertility, so it requires a call to specialists.

If the second phase on the chart is shorter than 10 days, then this is a clear sign of progesterone insufficiency. Usually, there is no decrease in temperature before the onset of menstrual bleeding. In this case, pregnancy is possible, but under the threat of interruption.

If there is a lack of estrogen in the body of a woman, the schedule will be chaotic, strikingly different from the norm. Also, this may be due to the influence of external factors (flights, excessive intake of alcohol, inflammation, etc.).

When the curve has no sharp temperature changes and is a monotonous graph, this is called the anovulatory cycle. This happens in healthy women, but not more than 1-2 times a year. If it repeats from cycle to cycle, then it can be a sign of infertility.

If after the second phase there is no decrease in temperature, then, most likely, the woman is pregnant.

The interpretation of the basal temperature charts, examples of which are presented above, require expert knowledge. Therefore, you should not make your own conclusions, put yourself a diagnosis and prescribe a treatment.

The advantages and disadvantages of the method

The advantages of the method are its absolute availability, simplicity and total absence of costs. When the basal temperature chart for ovulation is maintained by a woman regularly, it makes it possible to determine the days of ovulation, in time to recognize an early pregnancy or to detect hormonal abnormalities and contact a gynecologist.

However, there are also disadvantages in the method. This method is not very accurate because of the individual characteristics of each organism. Here are its main disadvantages:

• Do not give an opportunity to foresee when the ovulatory phase comes.
• Does not give exact information about when was ovulation.
• It does not guarantee even if there is a normal two-phase schedule, that ovulation really was.
• Can not give specific information about the quantitative content of progesterone in the blood.
• Does not provide data on the normal functioning of the yellow body.

To know exactly how informative the method is, it is necessary in the first couple of cycles to pass blood tests for female hormones and make ultrasound. If the data of the schedule and studies coincide, it means that a woman can safely keep a graph of basal temperature. The norm and the deviations displayed on the curve in this case will correspond to reality.

This method is convenient, simple and does not require financial expenses. If you follow all the rules exactly and know how to decipher the basal temperature chart, then it's very easy to find out the day of ovulation and plan the conception. However, in the presence of any deviations from the norm, it is worthwhile to consult a specialist to prevent the development of pathological processes.