Graph of basal temperature during pregnancy, normal and pathological menstrual cycle. basal temperature chart basal temperature chart

Having figured out what BBT is and how to measure it, let's move on to the topic of the basal temperature chart. We will learn how to build it correctly and what can be analyzed, guided by the results of this graph.

What happens to BT during one cycle

During each menstrual cycle, a woman's BBT changes under the influence of certain hormones.

In the first phase, when the egg grows and matures, estrogen activity predominates. At this stage, BBT is considered "low", and this period is called hypothermic. A day or two before the onset of BT reaches its lowest value (36.7-36.9).

When ovulation occurs, the corpus luteum begins to work at the site of the ruptured follicle, which produces the pregnancy hormone progesterone. It affects the structures of thermoregulation and BT begins to grow.

After the release of the egg, the second half of the menstrual cycle begins, the stage of "high" temperature or the hyperthermic rise of the curve. It is characterized by low estrogen and high progesterone.

The temperature difference between these two periods can be 0.5-1 degrees. During bleeding during menstruation, BT fluctuates within 37 degrees, and then begins to decline and this two-phase cycle repeats again.

The figure shows what a normal basal temperature chart looks like.

How to make such a schedule yourself

In order to draw a graph of basal temperature, the patient will need a special form or a pre-prepared template, where she will enter the results daily. You can print such a template by downloading from the Internet, or draw it yourself by hand.

The figure shows what the chart template looks like.

Every day at the same time in the morning, a woman takes measurements of BBT and fixes them in this table. The table takes into account not only the results of measurements, in a separate column you need to enter additional information about what could cause an unscheduled rise or decrease in BT, for example, alcohol intake or a viral infection.

After the end of one cycle, the woman connects the points obtained and, together with the specialist, analyzes the results of the graph.

Important! Considering that even normally a woman has anovulatory cycles, BBT measurements should be carried out for at least 3-4 months in a row in order to follow the dynamics of the process.

How to evaluate basal temperature charts

Recall once again what the calendar of an ideal two-phase chart looks like.

And now we will analyze examples of various deviations from the norm in the first and second phases and find out what they can mean.

Lack of estrogen and progesterone

In these situations, in the second phase, either there is no increase in the curve or it is very weak by 0.3-0.4 degrees.

If such results are recorded constantly, then this may indicate a malfunction in the body, which leads to secondary infertility.

Important! A woman will be able to conceive a child with this pathology, but low progesterone values ​​can cause spontaneous miscarriage. Therefore, even pregnant women should understand their BT schedule.

Insufficiency of the second phase in the II-phase cycle

A calendar with such a schedule is characterized by a short second period, and the graph curve begins to rise just before menstrual bleeding. This happens when there is a violation of the production of progesterone.

Anovulatory cycle

It is characterized by the absence of changes in the graph curve both in the first and in the second phase. The egg does not leave the follicle and, accordingly, the conception of a baby is impossible.

Normally, once a year and less often, a woman may experience such a situation, but its repetition for several months in a row indicates the presence of a pathology in the body.

Atypical graphic curve

The calendar shows ups and downs of the chart curve that are not typical for either type. It happens with a lack of estrogen and under the influence of random causes (virus, drugs, etc.).

What causes high temperature in the first phase

We found out that the first period is a phase of low values ​​(36.7-36.9), let's consider in what situations a deviation from the norm can be observed:

• insufficiency of female hormones (estrogen). At this time, estrogens are predominant. If their synthesis is lowered, then in the first phase BT can rise above the usual values, and in the second phase it continues to rise and remains at an elevated level, since progesterone begins to work;
• inflammatory processes in the ovaries. Inflammation can cause an abnormally high curve in the first phase. On such a graph, it is very easy to miss, since the rise in temperature due to inflammation is mistakenly confused with ovulation, and then miss the true temperature peak during the period of ovulation. The figure shows what this might look like;

• inflammation of the lining of the uterus (endometriosis). This process is characterized by the absence of a decrease in temperature after menstrual bleeding, and it continues to stay at the level of high values ​​(37.1-37.3). The first period begins with an elevated temperature, which gradually decreases and rises again by the time of ovulation;
• during pregnancy. If the egg has been successfully fertilized, then the corpus luteum continues to produce progesterone, which maintains a high temperature at the time when the first period is calculated to begin. Measurements of an increase in BBT in the first phase are accompanied by a delay in menstrual bleeding.

Important! One-time increases or decreases in temperature are unlikely to signal inflammation. It cannot begin and end in one day. Such errors are more likely to be due to incorrect measurement of BBT or other random reasons.

Why is there a low temperature in phase II

The second phase, unlike the first, is considered a period of high temperature values ​​​​(37.1-37.3 degrees). Let's analyze when BT does not increase in the second phase:

The correct construction and analysis of BT charts helps to suspect the presence of various pathological processes and calculate the time of the onset of favorable days for conception. This research method is simple, but diagnostically inaccurate, so if in doubt, you need to contact the doctor for an additional examination.

Not many women know how to measure and graph basal temperature correctly, but all representatives of the weaker sex should have this skill. After all, the measurement of basal temperature is necessary not only for any pathology, but will help you deal with your body and shed light on many questions.

What does the concept of "basal temperature" mean?

Basal temperature is the lowest body temperature that was recorded after a long state of rest, that is, sleep. Basal temperature is measured in the rectum, in the vagina or in the mouth. Unlike the true temperature, the basal temperature is always slightly higher (only a couple of tenths of a degree). Gynecologists believe that the most indicative is the basal temperature measured in the rectum, so its other name is rectal temperature.

The need to measure basal temperature

Measuring basal temperature and drawing up its schedule is one of the tests functional diagnostics. And although this method has been used for a long time, it has not lost its relevance to this day, since the measurement of basal temperature not only helps in the diagnosis of gynecological diseases, but the method itself is simple and cheap.

In what cases is the measurement of basal temperature indicated:

• the desire to become pregnant, and this requires setting the day of ovulation;
• protection against unwanted pregnancy, that is, the definition of so-called safe days;
• as an additional diagnostic method for inflammatory diseases of the pelvic organs;
• disruptions in hormonal regulation (, habitual miscarriage, ovarian dysfunction);
• infertility (it doesn't matter which partner is "guilty");
• establishing the duration of the phases of the menstrual cycle and ovulation;
• delayed menstruation and establishing its cause (possibly pregnancy);
• threatening or incipient miscarriage (assessment of the effectiveness of treatment and positive/negative dynamics);
• calculate the time of the next menstruation;
• desire to become pregnant with a child of a certain gender.

In order for the compiled schedule of basal temperature to be as informative as possible, its measurement must be carried out for (at least) three menstrual cycles and without interruption (one month the temperature was recorded, and the next not - incorrectly). Firstly, this need is due to the fact that even a healthy woman can have one or two anovulatory cycles during the year, and, secondly, it is possible to identify the influence of certain circumstances in one cycle, which, accordingly, makes the graph indicative ( and for comparison, there are several other menstrual cycles).

But the main thing that every woman should know is that measuring basal temperature while taking hormonal contraceptive pills is an absolute waste of time, since the artificial hormones contained in the pills suppress both ovulation and the production of their own hormones.

How to measure basal temperature correctly

In order for the compiled graph to display the correct results, and therefore be able to help in the diagnosis of pathology, you need to know how to measure the basal temperature correctly. The main condition for measuring temperature is responsibility and discipline. The list includes a few simple rules:

• temperature measurement is carried out immediately after waking up (preliminary “trips” to the toilet, drink water, etc. are excluded);
• sleep duration should be at least 3 hours, and preferably 6;
• once the thermometer is in place, do not move or keep movement to a minimum for the duration of the measurement (motor activity increases the temperature);
• temperature measurement must be carried out at a certain time (plus or minus an hour);
• a mercury thermometer is preferable for measuring basal temperature;
• the thermometer should be "at hand" (on the bedside table or table);
• when measuring temperature in the mouth or in the vagina, the measurement time is at least 5 minutes, and when measuring in the rectum, at least 3 minutes;
• temperature measurement is also performed on the days of menstruation;
• shake the mercury thermometer in the evening;
• record temperature data immediately after measurement;
• the measurement is carried out by one method (if it was carried out in the rectum, continue to measure the temperature rectally;
• the thermometer must be one, it is not allowed to replace it.

What thermometer to measure basal temperature?

When determining the temperature in the rectum with an electronic thermometer, you should follow the rules for using the device. When the temperature measurement process is completed, the thermometer beeps, which means that it must be removed. The final value must be recorded not immediately after extraction, but after 0.5 - 1 minute, because the temperature on the scale will rise for some time.

How to chart your basal temperature

For convenience, both compiling and reading the basal temperature graph, it should be placed on a double notebook sheet in a cage. The days of the menstrual cycle and the date are marked horizontally, and the basal temperature readings are marked vertically. From the point of 37 degrees horizontally, a red line should be drawn parallel to the line of the days of the cycle. This is a control line that will make it easier to read the chart and highlight the phases of the menstrual cycle and ovulation.

A separate column (below, under the horizontal line) should make “highlights”. The quality and quantity of vaginal discharge is related to the phase of the menstrual cycle. For example, on the eve and on the day of ovulation, they are liquid, plentiful and look like egg white, and in the second phase of the discharge they are thicker and have a milky color.

The column "miscellaneous" stands out even lower. Any force majeure circumstances are entered in this column: air travel, drinking alcohol, business trip, sex at night or in the morning, a short sleep, a cold, and so on.

The points that are plotted on the graph daily and denoting temperature values ​​are connected to each other. Thus, a broken line is obtained.

In a healthy woman, the menstrual cycle is divided into 2 phases: follicular and luteal, which is clearly visible on the graph, since the curve will be broken, first the temperature stays below 37 degrees, then jumps sharply and becomes above 37. Estrogens are active in the follicular phase, under the action of which the main follicle matures, so the graph will display a curve that is below 37 degrees. The follicular phase lasts about 12-14 days. On the eve of ovulation, the temperature drops by 0.2 - 0.4 degrees (preovulatory depression), and with its onset, the temperature rises and becomes 0.2 - 0.4 degrees above the 37-degree line. Then the luteal phase begins, which lasts for 14 days, and the graphic line will be above 37 degrees. Such an increase in temperature in the second phase is explained by the action of progesterone, which affects the center of thermoregulation. Before menstruation, the level of progesterone drops, which means that the schedule will decrease. If the temperature remains the same (above 37), besides, menstruation does not begin, this indicates a possible pregnancy.

We measure basal temperature during pregnancy

A basal temperature chart can be the first sign of pregnancy before a missed period. As mentioned above, basal temperature data fluctuate and depend on the phase of the menstrual cycle, which is determined by sex hormones. If in the follicular (first) phase the temperature should normally be below 37 degrees, then in the luteal or second phase the temperature will rise above 37 and stay at this level for about 14 days (plus or minus 2 days). On the eve of ovulation, it retracts, and immediately after the release of the egg from the ovary, it rises by 0.4 - 0.5 degrees and begins to decline only before the start of the next menstruation. If the temperature does not decrease on the eve of the expected menstruation and still remains above 37 degrees, then pregnancy can be assumed. The absence of menstruation on time plus an increased basal temperature requires a pregnancy test, which in 99% of cases will be positive.

The method of determining a probable pregnancy by basal temperature only works with ovulatory cycles that have been previously confirmed either by a basal temperature chart, or by ovulation tests, or by ultrasound. But if there is no ovulation, then no matter how long the temperature rises, this does not mean that conception has occurred, even if there is no next menstruation. For example, with hyperprolactinemia, when the pituitary gland produces increased amount prolactin, which is responsible for the production of milk, both signs may be present: a basal temperature above 37 degrees and the absence of menstruation.

From the foregoing, it becomes clear that basal temperature during early pregnancy remains high until the expected menstruation and does not decrease the rest of the time (against the background of a delay in menstruation and subject to confirmed ovulation in previous cycles).

Implant retraction

Speaking about the graph of basal temperature during pregnancy, one cannot remain silent about such a phenomenon as implantation retraction. Implantation is the process of introducing a fertilized egg into the lining of the uterus. That is, up to this point, even with the fusion of the egg and sperm, it is premature to talk about the onset of pregnancy. Only when the fertilized egg is fixed in the uterine wall and establishes a connection with the mother's body, we can assume that conception has occurred and the pregnancy continues to develop.

Against the background of implantation retraction, there is a slight (0.1 - 0.3 degrees) drop in temperature in the second phase of the cycle (the woman does not yet know about the onset of pregnancy and expects menstruation). If the moment of ovulation is clearly visible on the temperature chart, since the difference between ovulation and the beginning of the luteal phase of the cycle is 0.5 degrees, then implantation retraction is characterized by small fluctuations, so it is quite difficult to notice it. This phenomenon is noted approximately 7-9 days after the release of the egg from the ovary. This symptom is not a 100% guarantee of pregnancy. Additional criteria for this phenomenon are implantation bleeding (1-2 drops of pink or reddish color on underwear), which is also not observed in all women.

Ectopic pregnancy

Many women think that basal temperature during ectopic pregnancy does not rise. In fact, this statement is incorrect. It does not matter where the fertilized egg is fixed, in the uterus, in the tube or somewhere else, progesterone and hCG will be produced in any case.

Therefore, the basal temperature during an ectopic pregnancy will be above 37 degrees. From which it follows that it is impossible to determine the localization of the embryo from the graph of basal temperature.

Normal basal body temperature

It is not recommended to measure basal temperature for all women, and even more so, it is not measured for the entire period of pregnancy, but only up to 12 weeks. As a rule, the doctor recommends keeping a temperature chart for women from the group high risk miscarriage (difficult working conditions, complications of past pregnancies, such as miscarriages, premature births, etc.).

The basal temperature during pregnancy is normally in the range of 37.1 - 37.3 degrees, but its higher rates (up to 38) are not considered a pathology. Any deviation from the norm requires immediate medical advice.

Decreased basal body temperature

An unfavorable sign is a decrease in basal temperature in the first trimester of pregnancy. This indicates a threat of interruption or a missed pregnancy. Moreover, a drop in basal temperature is possible even before the appearance of clinical manifestations (bloody issues, aching or pulling pains in the lower abdomen and / or in the lower back). A drop in basal temperature is said to occur when it reaches 37 degrees and below. The same sign - low temperature is also observed during ectopic pregnancy, on the eve or at the time of rupture of the fallopian tube or tubal abortion.

Increase in basal body temperature

If the basal temperature is above 38 degrees for several days, this also indicates trouble in the body. Inflammatory processes of the genital organs, colds and other diseases are not excluded.

But the elevated temperature can be due to other factors:

• violation of measurement rules;
• taking medication;
• motor activity before and at the time of measurement, and others.

Measurement of basal body temperature (BT). Rules. Deciphering basal temperature charts

Basal temperature - this resting body temperature after at least 6 hours of sleep. In different phases of the menstrual cycle, the basal temperature in a woman is constantly changing under the influence of hormonal changes in the female body.

Measurement of basal body temperature BT - a simple functional test that every woman can learn at home. The method is based on the hyperthermic (temperature) effect of progesterone on the thermoregulatory center located in the hypothalamus.

Why you need a basal temperature chart

By drawing up a graph of fluctuations in basal temperature, you can absolutely accurately predict not only the phase of the menstrual cycle at the moment, but also suspect possible deviations from the norm. Let's list what exactly you might need basal body temperature measurement skill in everyday life:

1. If you want to get pregnant and cannot predict when ovulation occurs - a favorable moment for conceiving a child - the release of a mature egg capable of fertilization from the ovarian follicle into the abdominal cavity;
or vice versa - you do not want to get pregnant, thanks to the basal temperature (BT) you can predict “dangerous days”.
2. To determine pregnancy in the early stages with a delay in menstruation.
3. With regular measurement of basal temperature, you can determine the possible reason for the delay in menstruation: pregnancy, lack of ovulation or late ovulation.
4. If your gynecologist suspects that you have hormonal disorders, infertility in you or your partner: if pregnancy has not occurred after one year of regular intercourse, the gynecologist may recommend that you take a basal body temperature (BT) to determine possible causes infertility.
5. If you want to plan the gender of your unborn child.

How to measure basal temperature (BT) correctly

As you can see, the correct measurement of basal temperature (BT) helps to answer many important questions. Most women know why they need to measure basal temperature (BT), but few know how to properly conduct a study. Let's try to deal with this issue.

Firstly, you need to immediately understand for yourself that no matter what the obtained indicators of basal temperature (BT) are, this is not a reason for self-diagnosis, and even more so for self-treatment. Only a qualified gynecologist should deal with the interpretation of basal temperature charts.

Secondly, there is no need to draw any fleeting conclusions - basal body temperature (BT) needs at least 3 menstrual cycles to more or less accurately answer questions - when do you ovulate, do you have hormonal disorders, etc. d.

Basic rules for measuring basal temperature (BT)

1. It is necessary to measure basal temperature (BT) from the first day of the menstrual cycle (from the first day of menstruation), otherwise the graph will not reflect the full dynamics of changes.

2. You can measure your basal body temperature (BT) in your mouth, vagina, or anus, the latter is more preferable. Many gynecologists believe that it is the rectal method that is more reliable and gives fewer errors than all the others. In the mouth, you need to measure the temperature for about 5 minutes, in the vagina and in the rectum for about 3 minutes.
If you measured your basal temperature (BT) in one place, then the location of the thermometer and the duration of the measurement cannot be changed the next time you take a measurement. Today in the mouth, tomorrow in the vagina, and the day after tomorrow in the rectum - such variations are not appropriate and can lead to false diagnosis. Underarm basal temperature (BT) cannot be measured!

3. It is necessary to measure the basal temperature (BT) at the same time, preferably in the morning, immediately after waking up, without getting out of bed.

4. Always use the same thermometer - digital or mercury. If using mercury, be sure to shake well before use.

5. Write down the results immediately, while making notes if there was something on that day or the day before that could affect the basal temperature (BT) indicators: alcohol intake, flight, stress, acute respiratory infections, inflammatory diseases, elevated exercise stress, sexual intercourse the night before or in the morning, reception medicines- sleeping pills, hormones, psychotropic drugs, etc. All these factors can affect the basal temperature and make the study unreliable.

When taking oral contraceptives, measuring BBT does not make any sense!

Thus, in order to make a complete chart of basal body temperature (BT) fluctuations, you will need to label the indicators:
- date of the calendar month;
- day of the menstrual cycle;
- indicators of basal temperature;
- the nature of the discharge from the genital tract on a certain day of the cycle: bloody, mucous, viscous, watery, with yellowness, dry, etc. It is important to note this for the sake of completeness on the chart, as the discharge from the cervical canal becomes more watery during ovulation;
- notes as necessary by a certain day: we enter there all the provoking factors listed above, which may affect the change in BT. For example: I took alcohol the day before, didn’t sleep well or had sex in the morning before the measurement, etc. Notes must be made, even insignificant ones, otherwise the resulting graphs will not correspond to reality.

Generally speaking, your basal temperature records should look like this in a table:

Date Day mts BT Highlights Notes

5 July 13th 36.2 Watery, transparent Drank wine the day before
July 6 14th 36.3 viscous, transparent _________
July 7 15th 36.5 white, viscous _________

Normal basal temperature chart

Before you start drawing up a schedule for basal temperature (BT), you need to know how the basal temperature should normally change under the influence of hormones?

The menstrual cycle in a woman is divided into 2 phases: follicular (hypothermic) and luteal (hyperthermic). In the first phase, the follicle develops, from which the egg is subsequently released. In the same phase, the ovaries intensively produce estrogens. During the follicular phase, BT is below 37 degrees. Then ovulation occurs - in the middle of 2 phases - approximately on the 12-16th day of the menstrual cycle. On the eve of ovulation, BBT drops sharply. Further, during and immediately after ovulation, progesterone is released and BT rises by 0.4-0.6 degrees, which is a reliable sign of ovulation. The second phase - luteal, or it is also called the corpus luteum phase - lasts about 14 days, and if conception does not occur, it ends with menstruation. In the phase of the corpus luteum, very important processes take place - a balance is maintained between low levels of estrogen and high levels of progesterone - thus the corpus luteum prepares the body for a possible pregnancy. In this phase, the basal body temperature (BT) is usually kept at around 37 degrees and above. On the eve of menstruation and in the first days of the cycle, the basal body temperature (BT) again drops by about 0.3 degrees and everything starts anew. That is, normally, every healthy woman should have fluctuations in basal temperature (BT) - if there are no ups and downs, then we can talk about the absence of ovulation, and as a result, infertility.

Consider examples of basal temperature (BT) graphs, as they should be in normal and pathological conditions. The basal temperature (BT) graph that you see below reflects two normal physiological conditions that a healthy woman can have: 1-lilac curve - basal temperature (BT), which should be at normal menstrual cycle ending with menstruation; 2 - light green curve - basal temperature (BT) of a woman with a normal menstrual cycle, we will end in pregnancy. The black line is the ovulation line. The burgundy line is a mark of 37 degrees, it serves for visualization of the graph.

Now let's try to decipher this chart of basal temperature. Please note that a mandatory sign of basal temperature (BT) is normally a two-phase menstrual cycle - that is, both the hypothermic and hyperthermic phases should always be clearly visible on the graph. In the first phase, basal temperature (BT) can range from 36.2 to 36.7 degrees. We observe these fluctuations on this chart from days 1-11 of the cycle. Further, on the 12th day, BBT drops sharply by 0.2 degrees, which is a harbinger of the onset of ovulation. On the 13-14th day, a rise is visible immediately after the fall - ovulation occurs. Further, in the second phase, the basal temperature (BT) continues to rise by 0.4-0.6 degrees compared to the first phase - in this case, up to 37 degrees and this temperature (marked with a burgundy line) is kept until the end of the menstrual cycle and before the start menstruation falls - on the 25th day of the cycle. On the 28th day of the cycle, the line breaks, which means that the cycle has ended and a new menstrual cycle has begun. But another option is also possible - the light green line, as you can see, does not fall, but continues to grow to 37.1. This means that a woman with a light green line on the basal temperature (BT) chart is most likely pregnant. False-positive results of measuring basal temperature (an increase in basal temperature in the absence of a corpus luteum) can occur with acute and chronic infections, as well as with some changes in the higher parts of the central nervous system.

Important to know when charting your basal temperature!

1. Normally, the menstrual cycle in a healthy woman is from 21 to 35 days, most often 28-30 days, as in the graph. However, for some women, the cycle may be shorter than 21 days, or vice versa, longer than 35. This is a reason to contact a gynecologist. Maybe it's ovarian dysfunction.

2. The graph of basal temperature (BT) should always clearly reflect ovulation, which divides the first and second phases. Always immediately after the pre-ovulatory temperature drop in the middle of the cycle, a woman ovulates - on the chart this is the 14th day, marked with a black line. Therefore, the most optimal time for conception is the day of ovulation and 2 days before it. Using this chart as an example, the most favorable days for conception will be days 12, 13 and 14 of the cycle. And one more nuance: you may not detect a preovulatory decrease in basal temperature (BT) immediately before ovulation, but only see an increase - there is nothing to worry about, most likely ovulation has already begun.

3. The length of the first phase can normally change, lengthen or shorten. But the length of the second phase should not vary normally and is approximately 14 days (plus or minus 1-2 days). If you notice that the second phase is shorter than 10 days, this may be a sign of insufficiency of the second phase and requires a consultation with a gynecologist. In a healthy woman, the duration of the 1st and 2nd phases should normally be approximately the same, for example, 14 + 14 or 15 + 14, or 13 + 14, and so on.

4. Pay attention to the temperature difference between the averages of the first and second phases of the graph. If the difference is less than 0.4 degrees, this may be a sign of hormonal disorders. You need to be examined by a gynecologist - take a blood test for progesterone and estrogen. In approximately 20% of cases, such a monophasic BT-basal temperature chart without a significant temperature difference between the phases is a variant of the norm, and in such patients the hormones are normal.

5. If you have a delay in menstruation, and the hyperthermic (increased) basal temperature of BT lasts more than 18 days, this may indicate a possible pregnancy (light green line on the graph). If menstruation nevertheless came, but the discharge is rather meager and at the same time the basal temperature of BT is still elevated, you urgently need to contact a gynecologist and take a pregnancy test. Most likely - these are signs of a miscarriage that has begun.

6. If the basal temperature of BT in the first phase rose sharply for 1 day, then fell - this is not a sign of concern. This is possible under the influence of provoking factors that affect changes in basal temperature (BT).

Now let's look at examples of BT basal temperature charts for various gynecological pathologies:

The graph is monophasic, i.e. almost without significant temperature fluctuations of the curve. If the rise in basal temperature (BT) in the second phase is weakly expressed (0.1-0.3 C) after ovulation, then this possible signs lack of hormones - progesterone and estrogen. You need to take a blood test for these hormones.

If ovulation does not occur and the corpus luteum produced by progesterone does not form, then the basal temperature (BT) curve is monotonous: there are no pronounced jumps or drops - ovulation does not occur, respectively, and a woman with such a basal temperature (BT) schedule cannot become pregnant. An anovulatory cycle is normal in a healthy woman if such a cycle occurs no more than once a year. Accordingly, during pregnancy and lactation, the absence of ovulation is also the norm. If all of the above does not apply to you and this situation is repeated from cycle to cycle, you definitely need to contact a gynecologist. Your doctor will prescribe hormone therapy for you.

The basal temperature of BT rises a few days before the end of the cycle due to hormonal deficiency and does not decrease immediately before menstruation, there is no characteristic preovulatory retraction. The second phase lasts less than 10 days. It is possible to get pregnant with such a schedule of basal temperature (BT), but there is a high probability of miscarriage. We remember that the hormone progesterone is normally produced in the second phase. If the hormone is not synthesized in sufficient quantities, then BT rises very slowly, and the pregnancy may be terminated. With such a schedule of basal temperature (BT), it is necessary to pass an analysis for progesterone in the second phase of the cycle. If progesterone is lowered, then hormonal preparations - gestagens (Utrozhestan or Duphaston) are necessarily prescribed in the second phase. Pregnant women with low progesterone are prescribed these drugs for up to 12 weeks. With a sharp withdrawal of drugs, a miscarriage may occur.

In the first phase, the basal temperature of BT under the influence of estrogens is kept within 36.2-36.7 C. If the basal temperature of BT in the first phase rises above the indicated mark and if you see sharp jumps and rises on the graph, then most likely there is a lack of estrogens. In the second phase, we see the same picture - ups and downs. On the graph, in the first phase, the basal temperature of BT rises to 36.8 C, i.e. above the norm. In the second phase, there are sharp fluctuations from 36.2 to 37 C (but with a similar pathology they can be higher). Fertility in these patients is drastically reduced. For the purpose of treatment, gynecologists prescribe hormone therapy. Seeing such a graph, one should not rush to draw conclusions - such a picture can also be observed in inflammatory gynecological diseases, when everything is in order with estrogens, for example, with inflammation of the appendages. The chart is shown below.

You can see on this graph with sharp ups and downs that, due to the inflammatory process, it is problematic to determine when ovulation occurred, since the basal temperature of BT can increase both during inflammation and during ovulation. On the 9th day of the cycle, we see a rise that can be mistaken for an ovulatory rise, but this is most likely a sign of an inflammatory process that has begun. This basal temperature (BT) chart proves once again that it is impossible to draw conclusions and make diagnoses based on the basal temperature (BT) chart of one cycle.

We remember that at the beginning of the menstrual cycle, the basal temperature of BT is lowered. If the temperature at the end of the previous cycle decreased, and then rose sharply to 37.0 with the onset of menstruation and does not decrease, as can be seen on the graph, it may be a formidable disease - endometritis and you urgently need treatment from a gynecologist. But if you have a delay in menstruation and at the same time the basal temperature of BBT remains elevated for more than 16 days from the start of the rise, you are probably pregnant.

If you notice that during 3 menstrual cycles you have stable changes on the chart that do not correspond to the norm, you need to consult a specialist.

So, what should alert you when compiling and deciphering basal temperature (BT) charts:

Graphs of basal temperature (BT) with low or high temperature throughout the cycle;
- cycles less than 21 days and more than 35 days. This may be a sign of ovarian dysfunction, clinically manifested by bleeding in the middle of the menstrual cycle. Or there may be a different picture - the cycle is always lengthened, which is expressed in constant delays in menstruation for more than 10 days, while there is no pregnancy;
- if you observe a shortening of the second phase according to the charts;
- if the schedules are anovulatory or the manifestations of ovulation are not clearly expressed on the schedule;
- graphs with high temperature in the second phase for more than 18 days, while there is no pregnancy;
- monophasic graphs: the difference between the first and second phase is less than 0.4 C;
- if the BT schedules are absolutely normal: ovulation occurs, both phases are complete, but pregnancy does not occur within a year with regular unprotected intercourse;
- sharp jumps and rises in BT in both phases of the cycle.

If you follow all the rules for measuring basal temperature, you will discover a lot of new things. Always remember that you do not need to draw any conclusions on the basis of the obtained graphs. This can only be done by a qualified gynecologist, and then only after additional research.

Obstetrician-gynecologist, Ph.D. Christina Frambos

Measurement of basal body temperature (BBT or BBT) is a home diagnostic method that allows you to get information about the phase of the menstrual cycle, the approach and onset of ovulation, the state of the hormonal background, confirms pregnancy and gives an idea of ​​the nature of its course. It is also used as natural way contraception. BT is the lowest temperature mark that the body reaches in a state of complete rest, in particular during sleep.

Today, the measurement of basal temperature and the analysis of the graphs obtained during ovulation are rarely used in medical practice. Modern equipment, the availability of ultrasound reduce the relevance of this study. However, the method is suitable for self-control, is easy to use at home. Reviews of women confirm this.

What is the method based on?

The body temperature of a woman depends on many factors, the main of which is the change in the concentration of sex hormones during the menstrual cycle. Moreover, fluctuations can be observed not even by weeks, but by hours and minutes.

• First phase of the cycle. It is caused by the work of estrogen, under the influence of which the egg matures. During ovulation, levels of these hormones, regulated by luteinizing hormone (LH) and follicle-stimulating hormone (FSH), peak. As a result, a mature egg leaves the follicle for fertilization. An increased concentration of estrogens inhibits metabolic processes. Accordingly, the temperature in the tissues of the pelvic organs decreases.
• Second phase of the cycle. regulated by progestins. After ovulation, the concentration of these hormones increases and affects the formation of the endometrium. Also, progesterone is responsible for the normal course of the gestation period, for which it received the name “pregnancy hormone”. It stimulates thermoregulatory processes, which causes an increased basal temperature during pregnancy, before menstruation.

By measuring your basal temperature regularly over several months, you can determine how the phases of the menstrual cycle change, when ovulation occurs and the most likely days of conception. And also to find out if it took place.

For this, BT indicators are recorded every day in a special schedule. You can compose it yourself or use separate calendars, electronic applications.

Basal temperature indicators are rather relative, since the concentration of sex hormones is constantly changing in absolute terms. But this does not prevent this method from being one of the most common when planning a pregnancy due to its accessibility and information content. Also, knowing how the basal temperature changes, a woman can calculate the “safe” days for intimacy. Of course, subject to the stability of the cycle.

What does basal temperature show?

BT data are informative not only for the patient, but also for doctors. With the correct interpretation of the basal temperature graph, pregnancy can be determined, as well as:

• the relative concentration of estrogens and progestogens;
• approaching and onset of ovulation;
• deviations in the menstrual cycle;
• gestation pathology in the 1st trimester:
• suspicion of infertility;
• inflammatory processes in the genital organs.

6 rules for accurate results

Basal temperature is a very sensitive indicator, it can be affected by various factors. Therefore, the reliability of the conclusions depends only on the accuracy of the measurements. To achieve this, it is necessary to prepare for the construction of a BT schedule. Here are the main recommendations:

• limit sex - a few hours before measuring BBT;
• avoid stress- physical and emotional at the time of measurements;
• follow a diet - it is useful to limit the consumption of salty, fatty, fried foods;
• rest - before measuring basal temperature, you need to sleep for at least three hours.

It is necessary to measure basal temperature to determine ovulation by adhering to the following six rules.

1. Measurement frequency. Temperature readings should be recorded every day at the same time, marking them in a special graph (table). BBT measurement before and during menstruation should also be carried out.
2. Method . BTT is measured rectally - in the rectum. Oral and vaginal methods are not standard for this procedure and do not give accurate results.
3. Times of Day . The procedure is carried out in the morning. Before her, a woman must be in a state of complete rest (preferably sleep) for at least three hours. If there was a night shift at work the day before, a note should be made, as this may affect the result. It is pointless to conduct research in the evening - it is not informative at this time. Any physical activity should be limited. It is not even recommended to shake the thermometer before taking a measurement. Any activity changes the readings of the basal temperature, so the procedure is carried out at the moment of waking up and before getting out of bed.
4. Thermometer. Measurements should be carried out with the same thermometer, without changing mercury to electronic and vice versa. The most reliable readings are given by a mercury thermometer. It must be brought down to the minimum mark the night before, so as not to make efforts immediately before the procedure.
5. Duration. It is acceptable if a woman does not ovulate every month, especially closer to 40 years. Therefore, measurements should be carried out over a long period of time (at least 12 weeks). During pregnancy, it makes sense to measure up to the 2nd trimester, in the 3rd - the hormonal profile "at its discretion" changes the temperature.
6. Fixing indicators. It is best to mark the result immediately in the graph: since the difference in performance can be tenths of a degree, it is easy to forget or confuse them. As the points-marks of the basal temperature are put down, it is recommended to connect them with each other with lines. The graph should also note any factors that could affect the changes and validity of the data.

BT indicators: normal ...

There are relative norms of basal temperature, according to which it is possible to calculate, without the help of a specialist, what phase the cycle is in and the days of the highest female fertility.

• First phase (downgrade). Regulated by estrogen. It falls on days 1-13 of the cycle. Immediately after menstruation, the basal body temperature drops to 36.6-36.2°C.
• Ovulatory phase (oscillations). Peak activity of estrogens, FSH and LH. Lasts up to three days. A day or two on the eve of ovulation, BBT reaches 36.6-36.7 ° C. Basal temperature during ovulation rises by 0.1-0.4 ° C. After the rupture of the follicle and the release of the egg, the indicator is 37-37.4 ° C.
• Second phase (upgrade). It is regulated by progesterone and falls on days 16-28 of the cycle. During this period, BT is increased, its indicators vary between 37-37.4°C.

A few days before the onset of menstruation after ovulation, the level of progesterone rapidly decreases and a low basal temperature is again noted (within 36.8-36.6 ° C).

… and deviations

The basal temperature chart is a kind of indicator of a woman's health status. Deviations from the norm of BT indicators may indicate the following.

• Inflammation . If an elevated basal temperature is recorded before and during menstruation, this may indicate an inflammatory process in the organs of the reproductive system.
• The disadvantage of the second phase. BBT indicators in the luteal phase of the cycle below the norm indicate a progesterone deficiency.
• Individual characteristics of the organism. Small deviations (in tenths of a degree), which persist throughout the cycle, may be individual manifestations of the body's work.
• Offset ovulation. Moving the BBT jump horizontally along the schedule (to the right or left side) indicates early or late ovulation. Only a specialist can judge its success.
• double ovulation. It is characterized by two peaks of temperature increase. Moreover, the second one is possible in the late second phase, it is superimposed on the main value and therefore it is difficult to notice it.

no ovulation

If the cycle passed without ovulation, there are several options for basal temperature charts.

• High temperature in the first phase. When in the first half of the cycle the temperature is more than 36.6 ° C, this indicates that the level of estrogen is lowered. They are not enough to keep the temperature down, so the egg cannot mature.
• Smooth, not rapid rise in temperature. Such dynamics of BT during ovulation indicates the inferiority of the egg, which is why the follicle does not rupture.
• Sudden drop and then rise in temperature. In the second phase, this indicates that the egg has died.
• Consistent temperature readings throughout the cycle. The complete absence of a jump in basal temperature indicates the absence of ovulation.

Application hormonal drugs(for example, Duphaston, oral contraceptives) changes the basal temperature. Jumps depend on what type of hormones were used.

Values ​​during pregnancy

Often women resort to the method of measuring basal temperature in order to increase the chances of conception. Many rely on BBT readings to determine if a pregnancy has taken place and how it is progressing. This method is effective (including with twins, triplets), but only in the early stages - more modern and reliable diagnostic methods are available from the 2nd trimester.

Basal temperature during pregnancy may have the following indicators.

• Successful pregnancy. If fertilization has occurred, after ovulation, until the delay in menstruation, an increase in basal temperature is observed, which will continue to be kept at a high level. This is due to the influence of progesterone. If menstruation does not occur, and the temperature value has decreased, this indicates a cyclic failure. The norm of basal temperature in the early stages of pregnancy is in the range of 37-37.5 ° C.
• Frozen pregnancy. If the fact of conception is established, but there is a sharp decrease in BT during early pregnancy, which subsequently remains at the same level, this indicates the death of the embryo.
• Ectopic pregnancy. Most often, in the early stages, such cases do not affect the basal temperature and the schedule corresponds to the developing pregnancy.
• Risk of miscarriage . Often the cause of a miscarriage is progesterone deficiency, as indicated by a low basal body temperature both before and after the delay. If at the same time spotting appears, you need to sound the alarm and seek medical help.

Many factors can affect the basal temperature chart during pregnancy, so it should only be an auxiliary, and not the main method of monitoring health during this period.

Ovulation is a process that takes place in the body of a healthy woman, which is associated with the release of an egg into the fallopian tube for further fertilization. Knowing when you ovulate can help you plan your pregnancy or prevent unwanted conception. There are several methods for determining it, but the most accessible and simple is the measurement of basal body temperature.

What's this?

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

Many gynecologists advise women to keep their own basal temperature chart. Especially for those who are planning to replenish the family. The schedule of basal temperature during ovulation has its own characteristics. It allows you to calculate the most suitable day for getting pregnant. The basal temperature directly depends on the hormonal processes in the woman's body.

and its phases

Created for procreation, therefore, all the processes occurring in it are aimed at ensuring conception and preparing the body for pregnancy and childbirth. The menstrual cycle has three consecutive phases: follicular, ovulatory and luteal.

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

The second phase is ovulation itself. The walls of the follicle rupture, and the egg passes through the fallopian tube towards the sperm. The phase lasts about 2 days. If fertilization occurs, then the embryo attaches to the endometrium, if not, the egg dies. On a normal day, ovulation is at its lowest level for the entire cycle.

In the third phase, the production of progesterone begins. It is produced by the corpus luteum, which formed at the site of the ruptured follicle. The basal temperature after ovulation changes upwards - by 0.4-0.6 ° C. In this period female body prepares 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 during ovulation as a method characterizing hormonal changes in a woman's body was proposed in 1953 by the scientist Marshall. And now approved by WHO as an official method for detecting fertility. Its basis is a regular change in the concentration of progesterone in the blood. This hormone affects 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 drops by 0.2-0.3 ° C for 2 days, and then rises to 37-37.3 degrees and stays at this level almost until the end of the cycle. A normal basal temperature chart during ovulation is called biphasic.

Measuring your BBT can help you pinpoint a fertile day with high accuracy. According to statistics, it is known that the highest probability of getting pregnant will fall on the day before and after the temperature rise - 30% each. 2 days before the jump - 21%, 2 days after - 15%. Pregnancy can occur with a 2% chance if fertilization occurs 3 or 4 days before the temperature rises.

What is this method used for?

If you constantly draw up a graph of basal temperature, the norm and pathology begin to be traced literally after 2-3 cycles. The resulting curves can answer many questions. Therefore, gynecologists strongly recommend this method to solve the following problems:

• Determination of a favorable day for conception.
• Early diagnosis of pregnancy.
• As a method of contraception.
• Identification of malfunctions in the work of the sex glands.

Basically, basal temperature is measured to calculate the day the ovulatory phase of the cycle begins. This is the easiest and cheapest way. It is very easy to determine ovulation by basal temperature if you take measurements regularly and follow all the rules.

Correct measurement is the key to the effectiveness of the method

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

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

For measurements, both a digital and a mercury thermometer are suitable. But an infrared thermometer is absolutely not intended for this method, since it has a high probability of an error in the results. Since the basal temperature before ovulation and on the day it starts differ by only 0.2-0.3 ° C, such a thermometer may not show this difference. An electronic thermometer gives large errors if you do not follow the instructions for its use. The most accurate readings can be obtained using a mercury thermometer, but it requires special care when handling.

When the received indicators may be incorrect

It must be remembered that the basal temperature during ovulation, the norm of which is individual for each woman, can fluctuate depending on the influence of various factors. Often, external influences on the body lead to the fact that BBT indicators are highly distorted and have no informative value. These factors include:

• Flights, transfers, business trips.
• Stress.
• Excessive intake of alcohol.
• Taking psychotropic and hormonal drugs.
• Inflammatory processes in the body, fever.
• Increased physical activity.
• Short sleep.
• Failure to follow measurement instructions.
• Sexual intercourse a few hours before the measurement.

If something from the above list happened, then you should not trust the measurements. And the day on which there was a violation can be ignored in the construction of the schedule.

How to plot a basal temperature chart

To build a graph of basal temperature, it is necessary to take measurements every day and make notes in a specially designated notebook. The graph is the intersection of two lines at a right angle. vertical axis contains temperature data, for example, from 35.7 to 37.3 ° C, and the days of the menstrual cycle are located on the horizontal. Each cell corresponds to 0.1 °C and 1 day. After making the measurement, you need to find the day of the cycle on the graph, mentally draw a line up and put a dot in front of the desired temperature. At the end of the cycle, all points of the graph are connected, the resulting curve is an objective display of hormonal changes in the female body.

In the chart, you should indicate the current date and build a column for special notes. In order for the data to be sufficiently complete, you can describe your state of health, the symptoms that appear, or situations that could be reflected in a change in basal temperature.

If a woman is not very clear on how to plot a basal temperature, then a gynecologist from antenatal clinic will definitely explain how to do this, and also help to decrypt the received data.

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

Chart decoding

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

The overlapping (middle) line is built over 6 points of the follicular cycle without taking into account the first 5 days and days when the indicators deviated greatly due to external factors. This element has no meaning. But it is necessary for clarity.

The basal body temperature decreases on the day of ovulation, so in order to determine the day for a successful conception, you need to find successive points that are under the overlapping line. In this case, the temperature values ​​of 2 out of 3 points should differ by at least 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 that, you can observe a jump of the point up by 0.3-0.4 degrees. In this place, you need to draw an ovulation line. If there are difficulties with this method, then you can use the "finger" rule to plot. 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 resulting schedule, build an ovulation line.

The basal temperature after ovulation in the anus should be kept above 37 ° C for 2 weeks. Deviations in the duration of the second phase or a small jump in temperature indicate ovarian dysfunction or low productivity of the corpus luteum. If 2 cycles in a row the duration of the second phase does not exceed 10 days, then it is necessary to consult a gynecologist, since this is the main sign of progesterone deficiency of the luteal phase.

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

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

The normal ovulatory schedule consists of two phases. In the first one, an average temperature of 36.5-36.8 °C can be observed for 1-3 weeks, then a drop by 0.2-0.3 °C and a sharp rise to 37 °C and above. In this case, the second part of the schedule should be no shorter than 12-16 days, and before the onset of bleeding, there is a slight decrease in temperature. Graphically it looks like this:

You should also give examples of basal temperature charts in which pathology is traced. The curve in this case will differ from the norm in various ways. If there is, then the temperature jump will be no more than 0.2-0.3 ° C. This condition is fraught with infertility, therefore, it requires an appeal to specialists.

If the second phase on the graph is shorter than 10 days, then this is a clear sign of progesterone deficiency. 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 a woman's body, then the schedule will be chaotic, strikingly different from the norm. It may also be due to the influence of external factors (flights, excessive alcohol intake, inflammation, etc.).

When the curve does not have sharp jumps in temperature and is a monotonous graph, then this is called This happens in healthy women, but not more than 1-2 times a year. If this is repeated from cycle to cycle, then this may be a sign of infertility.

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

Deciphering the basal temperature charts, examples of which are presented above, require specialist knowledge. Therefore, you should not independently draw conclusions, diagnose yourself and prescribe treatment.

Advantages and disadvantages of the method

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

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

• It does not make it possible to predict when the ovulatory phase will come.
• Does not give accurate information about when ovulation occurred.
• It does not guarantee, even in the presence of a normal two-phase schedule, that ovulation really took place.
• Cannot give specific information about the quantitative content of progesterone in the blood.
• Does not provide data on the normal functioning of the corpus luteum.

In order to know exactly how informative the method is, it is necessary in the first couple of cycles to take blood tests for female hormones and do an ultrasound scan. If the data of the graph and research coincide, then the woman can easily keep a graph of basal temperature. The norm and 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 finding out the day of ovulation and planning conception is very easy. However, if there are any deviations from the norm, it is worth contacting a specialist to prevent the development of pathological processes.