A woman's basal temperature changes throughout menstrual cycle. The method of measuring it will help determine the day of ovulation, identify problems that prevent you from conceiving a child, and determine the onset of pregnancy.

What is basal temperature

Basal body temperature is measured in the mouth, rectum or vagina at complete rest. It changes on different days of the menstrual cycle. Typically, a woman’s readings are below 37°C before ovulation, that is, until the middle of the cycle. After the release of the egg, it may increase slightly and remain at this level throughout the second half of the cycle.

The first phase (days before ovulation) can have a different duration, which depends on the length of the menstrual cycle, but the second phase (after the release of the egg) usually lasts 14 days for a healthy woman. An increase in temperature can be seen on the graph; if daily measurements are taken, the difference in values ​​between the second and first phases of the cycle is more than 0.4°C.

1–2 days before the onset of menstruation, the basal temperature drops to its original values. The temperature does not drop only when pregnancy occurs. Thus, if its decrease is not observed, and menstruation does not begin, we can conclude that the egg is possibly fertilized.

Scheduling basal temperature helps determine the optimal time for conception, influence the gender of the unborn child, and avoid unwanted pregnancy, evaluate the work endocrine system, calculate the date of the next menstruation, diagnose pregnancy.

Rules for measuring basal temperature

Human body temperature fluctuates throughout the day due to the influence of various external factors: overheating and cooling, physical activity, stress, eating. Therefore, the true temperature can only be measured immediately after waking up in a state of rest. This indicator is called basal temperature.

In order for the results to be informative, you need to adhere to certain rules when determining your basal temperature:

• measure temperature only in the mouth, vagina, rectum, and not in armpit(better in the rectum);
• you need to start measuring on the first day of the cycle and conduct observations to draw up a schedule over several months;
• sleep for at least 5–6 hours continuously before measurement;
• don't get out of bed, don't talk, don't do sudden movements before measuring temperature;
• carry out measurements constantly at the same time;
• use the same thermometer.

When working on a basal temperature chart to determine pregnancy, deviations in measurement time of no more than 30 minutes are permissible

When drawing up a basal temperature chart, you should include information about factors that could affect the result: stress, illness, overwork. When planning a pregnancy, you can add to this data the dates of unprotected sexual intercourse and the nature of vaginal discharge.

Basal temperature during pregnancy

When pregnancy occurs, basal temperature changes. You can notice this on the graph.

There is a high probability of fertilization if:

• a potentially pregnant woman's temperature remains higher than in the first phase of the cycle for more than three days;
• with a two-phase schedule it is observed sharp drop temperature (implantation retraction) 5–10 days after ovulation with a subsequent rise.

The increase in temperature during ovulation is explained by the influence of hormones that prepare the walls of the uterus for fertilization and attachment of the fertilized egg. If the sperm fails to reach its target, the egg dies, the cycle starts over, and the temperature drops.

During fertilization, hormones continue to act, so the pregnant woman’s temperature rises to 37°C and above, remains at this level throughout the entire first trimester of pregnancy, after which it gradually decreases to normal values.

A sharp drop in basal temperature during pregnancy may indicate a lack of hormones, that is, a threat of miscarriage. If the measured indicators decrease in the first three months of pregnancy, you should definitely consult with an obstetrician-gynecologist. A significant increase in temperature may indicate various types of inflammatory processes in the body, which also requires the intervention of medical professionals.

Basal temperature is the body temperature at rest, when it is possible to calculate the state of the gonads and the system as a whole. It shows the lowest temperature readings, which are observed only at rest. This helps many women understand what phase they are in. Correct measurements and a schedule during the cycle help determine the period of ovulation when you can conceive a child or, conversely, engage in unprotected sex without consequences.

There are three successive phases of the menstrual cycle:

1. Follicular.
2. Ovulation.
3. Luteal.

At each stage there is a different level of hormones, which is reflected in the basal temperature. To obtain accurate data, it is necessary to take accurate measurements in the rectum, vaginal or.

Measuring rules

The main rules of measurement, which are noted on the website, are as follows:

1. Take your temperature no more than 30-60 minutes after waking up.
2. The duration of sleep before measurements should be at least 3 hours. More short period rest can distort the indicators.
3. Take measurements at the same time.
4. Measure the temperature in supine position, do not sit down.

If you take the temperature later, you may make a mistake. Notes should be made in the records at what time the measurements were taken. Every hour the temperature increases by 0.1 degrees.

The same thermometer should be used throughout the entire cycle to obtain more accurate data. It is better to use a digital thermometer that makes a sound when the measurement is completed. However, when using mercury thermometer you should hold it for 5 minutes. At the same time, it is not advisable to rise or move suddenly.

It is better to take measurements throughout the month, including monthly days, in order to create a schedule.

BT schedule

The basal temperature (BT) chart is drawn from the beginning of the last to the beginning of the new menstruation and then a new one is drawn. The dividing line is the period of ovulation, when the egg is released from the ovary. She divides the stages into before and after. Ovulation occurs in the middle of the menstrual cycle - on days 12-16.

The average cycle length is 28 days. This is the period from the start of bleeding of the previous menstruation to the first day of bleeding of the next. In some cases this period increases to 35 days. Sometimes the last point in the BT chart is 21 days.

What does the BT chart show?

1. Days of ovulation, which allows you to determine when to conceive.
2. Causes of infertility that only a doctor can identify.
3. Causes of delayed or supposed menstrual flow.
4. Identify sexually transmitted diseases, such as endometritis.

First phase

The follicular first phase is also called hypothermic, while the luteal phase is hyperthermic. From the names it becomes clear that in the first period the body temperature is slightly lower, and in the second – increased. In the follicular phase, a follicle is formed in which the egg matures. Estrogen is produced by the ovaries. Normal temperature during this period the temperature reaches 37°C. This is favorable for pregnancy.

Elevated temperatures during this period become the reasons why conception does not occur. If in the first phase the temperature remains at 37 degrees, and the basal temperature on the 17th day reaches 37.5 degrees, then insemination becomes problematic, even if the sperm has penetrated the female reproductive system.

Second phase

Ovulation is difficult to detect. In the second phase, the temperature decreases, and the next day it increases by 0.4-0.5 ° C. She stays like this until her period. On average, the second phase lasts 14 days.

A decrease in basal temperature during implantation indicates the activation of estrogen - hormones that affect the temperature inside the reproductive system. This decrease occurs for several hours, and then increases again.

The duration of the luteal phase can be short - 10-12 days, which indicates its insufficiency and inability to bear a fetus. A longer phase may indicate the appearance of a cyst in the corpus luteum or the beginning of pregnancy. Only a doctor can decipher the data.

Ovulation occurs somewhere in the middle of the cycle. Sometimes it may not happen at all. Its presence is indicated by an increase in temperature.

Indicators in the first phase

In the first phase, estrogens predominate, which control the temperature of the reproductive system. Normal values ​​are 36.2-36.5°C. If during this period the temperature rises to 36.5-36.8 ° C, then this indicates insufficient estrogen levels. IN in this case Gynecologists prescribe hormone therapy.

If the increase in temperature during the follicular period occurred within one day, then you should not worry. No pathologies can occur during such a period. Deviations should be judged not by a single indicator, but by the entire schedule, which is drawn up many times.

Indicators in the second phase

The second phase may also occur high performance temperature. This indicates estrogen deficiency. After the egg leaves the follicle, the temperature rises to 37°C or more, which interferes with conception. The mark of 36.8 degrees is observed very rarely.

Rectal measurements exceed those in the first phase by 0.4 degrees. This is considered normal. Less significant differences indicate problems that need attention.

Every woman's body is unique. He is not required to meet clear indicators. Sometimes increased or low temperature is a feature, not a disease. Measurement methods should also be taken into account. Differences of 0.2 degrees are quite normal.

Impact factors

It is necessary to take into account factors influencing BT indicators. They are:

• Drinking alcohol.
• Sexual relations before dawn or at night.
• Inflammation in the leg area.
• Stress.
• Various diseases.
• Sleeping with a heating pad under an electric blanket.

These factors should be noted in your notebook where you keep your BT chart. Gynecologists advise taking daily measurements for at least 3 months, which will help identify more accurate data and features.

If a woman wants to more accurately determine the day of ovulation, then she should take daily measurements and write them down in a notebook for six months, or better yet, a year. In this case, you should refuse to take hormonal medications And contraceptive device. Only the use of a condom is allowed.

Rising temperature as an indicator of pregnancy

All manipulations are done for the sake of conception. A rising temperature may be an indicator that pregnancy has begun. This becomes clear when, from the moment of ovulation until the onset of menstruation (when they should begin), a high temperature is noted. It rises to 37°C or more and does not subside. This indicator becomes unambiguous if such a high temperature is noted in the period before the onset of menstruation and its delay.

In the second phase, BT can also be high in the absence of pregnancy. It rises to 37 degrees and above and stays there. Its decrease occurs the day before the start of menstruation. Accordingly, if there is a delay and BT is high, then we can talk about pregnancy. Therefore, you should focus not only on pregnancy tests, but also on internal indicators temperature.

Gynecologists recommend waiting for a delay so that breast disease and high temperature before menstruation are not misleading. These factors are normal before normal menstruation. However, a delay in combination with such symptoms may already indicate the beginning of pregnancy.

Temperature changes during other processes

You should listen to your body. A situation may arise when a change in temperature indicates other processes, for example, a miscarriage. In this case, menstruation is scanty and BT is high. You should take a pregnancy test and visit a gynecologist.

An increase in basal temperature on the 22nd day and its absence before or on the first day of menstruation may be an individual feature or indicate inflammatory processes in the body.

If BT drops on day 25, then this indicates upcoming menstruation. Everything in a woman’s body happens normally.

Forecast

Basal temperature, of course, can help a woman determine the days of ovulation and even find out in advance that she is pregnant, but such indicators are not always unambiguous. The prognosis largely depends on a combination of many factors, not just resting body temperature.

Should be considered individual characteristics body. You can find out about them if you keep a BT chart for several months. Based on the indicators, it will become clear what is inherent in a particular female body at each phase and before menstruation. Also, you should not prematurely rejoice in pregnancy if BT is high before the onset of menstruation.

Various factors affect a woman's body. The seasonality of the year should be taken into account, which also affects the condition general health. After taking measurements for six months or a year, we can draw some conclusions. It is better to review the schedule with a gynecologist, who takes into account many factors. This will help either conceive a child or get rid of women's problems that interfere with getting pregnant.

Measuring basal body temperature (BBT or BBT) - home diagnostic method, which allows you to obtain information about the phase of the menstrual cycle, the approach and onset of ovulation, the state of hormonal levels, 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 level that the body reaches in a state of complete rest, in particular during sleep.

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

What is the method based on?

A woman’s body temperature depends on many factors, the main one of which is changes 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 estrogens, under the influence of which the egg matures. During ovulation, the levels of these hormones, regulated by luteinizing hormone (LH) and follicle-stimulating hormone (FSH), reach their peak. As a result, the mature egg is released from the follicle for fertilization. Increased concentration of estrogen 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. Progesterone is also responsible for normal course period of gestation, for which it received the name “pregnancy hormone”. It stimulates thermoregulatory processes, which causes increased basal temperature during pregnancy, before menstruation.

By regularly measuring your basal temperature 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 find out whether it took place.

To do this, BT indicators are entered into a special chart every day. You can create it yourself or use separate calendars and electronic applications.

Basal temperature indicators are quite relative, since the concentration of sex hormones is constantly changing in absolute values. But that doesn't stop me this method to be one of the most common when planning pregnancy due to its accessibility and information content. Also, knowing how basal temperature changes, a woman can calculate “safe” values ​​for intimacy days. Of course, provided the cycle is stable.

What does basal temperature show?

BT data are informative not only for the patient, but also for doctors. If you correctly decipher the basal temperature chart, you can determine pregnancy, as well as:

• relative concentration of estrogens and gestagens;
• approach and onset of ovulation;
• abnormalities in the menstrual cycle;
• pathology of pregnancy 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 and can be affected by various factors. Therefore, the reliability of the conclusions depends only on the accuracy of the measurements. To achieve this, you need to prepare to build a BT schedule. Here are the main recommendations:

• limit sex - a few hours before measuring the BTT indicator;
• 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 your basal temperature, you need to sleep for at least three hours.

To measure basal temperature to determine ovulation, it is necessary to adhere to the following six rules.

1. Measurement frequency. Temperature readings should be recorded at the same time every day, noting them in a special chart (table). BBT measurements should also be taken before and during menstruation.
2. Method. BBT 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 it, the woman must be in a state of complete rest (preferably sleep) for at least three hours. If the day before there was night shift at work, you should make a note, as this may affect the result. There is no point in conducting research in the evening - it is uninformative at this time. Any physical actions. It is not even recommended to shake the thermometer before measuring. Any activity changes the basal temperature readings, so the procedure is carried out at the moment of awakening 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. Gives the most reliable readings mercury thermometer. It needs to be brought down to a minimum level the night before, so as not to put effort into it immediately before the procedure.
5. Duration. It is acceptable if a woman does not ovulate every month, especially closer to 40 years of age. Therefore, measurements should be carried out over a long period of time (at least 12 weeks). During pregnancy, it makes sense to measure before the 2nd trimester, in the 3rd trimester - hormonal profile“at its own discretion” changes the temperature.
6. Recording indicators. It is best to note the obtained result immediately in the graph: since the difference in indicators can be tenths of a degree, they are easy to forget or confuse. As basal temperature markers are set, it is recommended to connect them with lines. The graph should also note any factors that could affect the changes and reliability of the data.

BT indicators: normal...

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

• First phase (downgrade). Regulated by estrogens. Occurs on days 1-13 of the cycle. Immediately after menstruation, the basal temperature drops to 36.6-36.2°C.
• Ovulatory phase (fluctuations). Peak activity of estrogen, FSH and LH. Lasts up to three days. A day or two before ovulation, BT reaches 36.6-36.7°C. Basal temperature during ovulation rises by 0.1-0.4°C. After the follicle ruptures and the egg is released, the indicator is 37-37.4°C.
• Second phase (increase). Regulated by progesterone and occurs on days 16-28 of the cycle. During this period, BT is increased, its values ​​vary between 37-37.4°C.

A few days before the onset of menstruation after ovulation, progesterone levels rapidly decrease 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 in 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.
• Disadvantage of the second phase. BBT levels in the luteal phase of the cycle that are below normal indicate progesterone deficiency.
• Individual characteristics of the body. Small deviations (in tenths of a degree) that persist throughout the entire cycle may be individual manifestations of the body’s functioning.
• Ovulation offset. Moving the BT jump horizontally according to 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 is possible in the late second phase, superimposed on the main value and therefore difficult to notice.

No ovulation

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

• 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 estrogen levels are low. There are not enough of them to control the temperature, so the egg cannot mature.
• Smooth rather than 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.
• Smooth temperatures throughout the entire cycle. Complete absence jumps in basal temperature indicate a lack of ovulation.

The use of hormonal drugs (for example, Duphaston, oral contraceptives) changes basal temperature. The jumps depend on what type of hormones were used.

Values ​​during pregnancy

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

Basal temperature during pregnancy can have the following indicators.

• Current pregnancy. If fertilization has occurred, after ovulation until menstruation is delayed, an increase in basal temperature is observed, which will subsequently remain at a high level. This is due to the influence of progesterone. If menstruation does not occur and the temperature has dropped, this indicates a cyclic failure. The normal basal temperature in early pregnancy is within 37-37.5°C.
• Frozen pregnancy. If the fact of conception is established, but is observed a sharp decline BT during early pregnancy, which subsequently remains at the same level, 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 miscarriage is progesterone deficiency, as indicated by low basal temperature both before and after the delay. If at the same time there were bloody issues, you need to sound the alarm and seek medical help.

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

Based on basal temperature, doctors can judge how a woman’s function is working. reproductive system. The popularity of this method is also explained by the fact that many women use it to plan pregnancy. But in order to correctly decipher its readings, you need to know what factors influence its fluctuations and how to correctly measure basal temperature.

What does basal temperature show?

Basal temperature (BT) is the temperature of a sleeping person . Its indicators are very closely related to the level of hormones in the blood. Female hormones, produced by a woman’s ovaries, affect thermoreceptors and create cyclic fluctuations in BBT.

When progesterone reaches its maximum level, basal temperature begins to rise in unison, and vice versa, the rise in estrogen reduces rectal temperature. The peculiarity of the blood supply to the ovaries makes it possible to detect these fluctuations primarily in the rectum, so in other places (in the armpit, in the mouth) these indicators may not be as accurate.

Throughout monthly cycle hormonal background exposed sudden changes, but overall it has a certain sequence. With the help of regular measurements of basal temperature, a woman can essentially find out how correctly and stably her reproductive system is working .

Why is basal temperature measured?

The process of measuring temperature is very painstaking, so many women wonder why they need to spend a lot of time on this activity.

Most often, the BT measurement method is used as home test for ovulation. But you need to completely rely on this method only if the woman does not have any pathologies of the menstrual cycle .

Thermometry technique

The rules for measuring basal temperature are quite strict; failure to comply with them can significantly reduce the result obtained.

Therefore, before you start charting rectal temperature, you should thoroughly study all the intricacies of this procedure:

1. BT is measured while lying down immediately after waking up. Three hours before this, a woman should not get out of bed. Only in this case the indicator will be accurate. The thermometer should be at hand, since when you wake up, you do not need to make sudden movements or turns.
2. Basal temperature is measured in the rectum. It is also allowed in the vagina, armpit or mouth. Each time you need to measure in the same place.
3. The temperature is measured for 5 minutes, after which the exact data must be recorded in a special table.
4. It is better to use a mercury thermometer for measurements. Its indicators, unlike electronic ones, are always more accurate. You need to shake off the mercury thermometer immediately before taking measurements, this will affect the accuracy.
5. The readings of a mercury thermometer and an electronic thermometer may differ, so you should always use the same thermometer.
6. Basal temperature must be measured at the same time of day - early in the morning from 6 to 8 o'clock.
7. The procedure is carried out daily, even during menstruation.
8. It is necessary to record the readings without delay, as there is a risk that the data will be forgotten.

Factors influencing BT indicators

One of the most serious shortcomings This method is based on the fact that basal temperature is sensitive to certain changes in the body. In this case, the overall picture of the graph may be distorted.

So, what reasons can cause fluctuations in rectal temperature:

• A few hours after intercourse, BBT may be higher than normal, especially if measured in the vagina.
• Alcohol taken the day before.
• Imbalance in the gastrointestinal tract.
• Strong physical fatigue, exhaustion.
• Cold either chronic illness, general rise in temperature.
• Taking medications - sedatives, sleeping pills, hormonal drugs.
• Sleep less than 6 hours.
• Severe stress.
• Intense mental work.
• Climate change, time zone change.
• Smoking.

In order to be able to track how this or that factor affected the temperature and not be misled by false indicators, you need to make appropriate notes on the side of the graph itself. In addition, doctors recommend entering data on discharge into a table: color, consistency, quantity .

For those who are accustomed to using the Internet in all areas of life, there are special services for building online graphs that automatically make calculations and notify about possible deviations.

Basal temperature norms

Measuring and recording the temperature is only half the battle. To understand these numbers and graphs, you need to know what a standard graph should look like, and based on this, draw conclusions about the state of your body.

In medicine, there are five types of temperature curve. The very first type is typical for normal cycle. The remaining four indicate a deficiency of one or another hormone.

Provided that a woman’s body works without deviations, the basal temperature during menstruation will be in the range of 36.4-36.7 degrees. After their completion, shortly before ovulation, it drops sharply to 36.3-36.2. Then the indicator grows rapidly and within a day rises to 36.6-36.7.

After ovulation, it remains at 37 degrees for another 10 days. And before menstruation, it drops again to 36.6.

When taking oral contraceptives, BT will be approximately the same throughout the entire cycle.

This is what a normal curve should look like

If the graph shows strong deviations from the norm, you should definitely see a doctor, but only if the woman is sure that she did everything correctly and the BT measurements were carried out without violations.

Measuring basal temperature (BT). Rules. Decoding basal temperature charts

Basal temperature - This body temperature at rest after at least 6 hours of sleep. IN different phases During the menstrual cycle, a woman’s basal temperature constantly changes under the influence hormonal changes in the female body.

Measuring 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 thermoregulation center located in the hypothalamus.

Why do you need a basal temperature chart?

By drawing up a graph of fluctuations in basal temperature, you can 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 skill of measuring basal temperature in everyday life:

1. If you want to get pregnant and cannot predict when ovulation occurs, a favorable moment for conceiving a child is the release of a mature, fertilizing egg from the ovarian follicle into the abdominal cavity;
or vice versa - you don’t want to get pregnant, thanks to basal temperature (BT) you can predict “dangerous days”.
2. To determine pregnancy in the early stages with a delay in menstruation.
3. By regularly measuring basal temperature, you can determine the possible cause of a delay in menstruation: pregnancy, lack of ovulation or late ovulation.
4. If your gynecologist suspects that you have hormonal disorders, you or your partner are infertile: if after one year of regular sexual activity pregnancy has not occurred, the gynecologist may recommend that you measure your basal temperature (BT) to determine possible reasons infertility.
5. If you want to plan the gender of your unborn child.

How to measure basal temperature (BT) correctly

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

Firstly, you need to immediately understand for yourself that no matter what the basal temperature (BT) values ​​obtained are, this is not a reason for self-diagnosis, and even less so for self-medication. Only a qualified gynecologist should decipher basal temperature charts.

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

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 basal temperature (BT) in the mouth, vagina or anus, the latter is more preferable. Many gynecologists believe that the rectal method is more reliable and produces fewer errors than all others. You need to measure the temperature in the mouth for about 5 minutes, in the vagina and rectum for about 3 minutes.
If you measured your basal temperature (BT) in one place, then the next time you take a measurement, the location of the thermometer and the duration of the measurement cannot be changed. 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. Basal temperature (BT) cannot be measured under the armpit!

3. You need to measure your 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 you use mercury, remember to shake before use.

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

When taking oral contraceptives, measuring BT makes no sense!

Thus, to compose full schedule fluctuations in basal temperature (BT) you will need to mark the indicators:
- date of the calendar month;
- day of the menstrual cycle;
- basal temperature indicators;
- the nature of discharge from the genital tract on a certain day of the cycle: bloody, mucous, viscous, watery, yellowish, dry, etc. It is important to note this to complete the picture of the chart, since during ovulation, discharge from cervical canal become more watery;
- notes as necessary for a specific day: we enter there all the provoking factors listed above that 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.

In general, your basal temperature records should look something like this in table form:

Date Day mts BT Highlights Notes

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

Normal basal temperature chart

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

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

Let's look at examples of basal temperature (BT) graphs, what they should be normally and in pathology. The basal temperature (BT) chart that you see below reflects two normal physiological conditions that a healthy woman may have: 1-lilac curve - basal temperature (BT), which should be during a normal menstrual cycle, ending with menstruation; 2- light green curve - basal temperature (BT) of a woman with a normal menstrual cycle, ending in pregnancy. The black line is the ovulation line. The burgundy line is the 37 degree mark, used for clarity of the graph.

Now let's try to decipher this basal temperature graph. 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, BT sharply drops by 0.2 degrees, which is a harbinger of the beginning of ovulation. On the 13-14th day, a rise is visible immediately after the fall - ovulation occurs. Next - to the second phase - 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) remains until the end of the menstrual cycle and drops before the start of menstruation - on the 25th day of the cycle. On the 28th day of the cycle, the line is interrupted, 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 most likely a woman with a light green line on the basal temperature (BT) chart is pregnant. False Positives measurements of basal temperature (an increase in basal temperature in the absence of the corpus luteum) can be taken during 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 for a healthy woman ranges 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, conversely, longer than 35. This is a reason to contact a gynecologist. Perhaps this is ovarian dysfunction.

2. The basal temperature (BT) chart should always clearly reflect ovulation, which divides the first and second phases. Always immediately after a pre-ovulatory drop in temperature 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 graph as an example, the most favorable days For conception there will be 12,13 and 14 days of the cycle. And one more nuance: you may not detect a pre-ovulatory decrease in basal temperature (BT) immediately before ovulation, but only see an increase - there is nothing wrong with that, 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 your second phase is shorter than 10 days, this may be a sign of insufficiency of the second phase and requires 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 average values ​​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 estrogen. In approximately 20% of cases, such a monophasic graph of basal temperature BT-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 BT temperature lasts more than 18 days, this may indicate a possible pregnancy (light green line on the graph). If menstruation does occur, but the discharge is quite scanty and the basal BT temperature is still elevated, you urgently need to see a gynecologist and take a pregnancy test. Most likely these are signs of an incipient miscarriage.

6. If the basal BT temperature 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 graphs of basal BT temperature for various gynecological pathologies:

The schedule 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 have 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 monotonic: there are no pronounced jumps or falls - ovulation does not occur, and accordingly, a woman with such a basal temperature (BT) curve cannot become pregnant. An anovulatory cycle is normal for 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 repeats from cycle to cycle, you definitely need to contact a gynecologist. The doctor will prescribe you hormonal treatment.

The basal temperature of the BT increases several 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 basal temperature (BT) schedule, but there is a high probability of miscarriage. We remember that normally the hormone progesterone is produced in the second phase. If the hormone is synthesized in insufficient quantities, BT rises very slowly and the pregnancy may be terminated. With such a basal temperature (BT) schedule, it is necessary to take a progesterone test in the second phase of the cycle. If progesterone is low, then it must be prescribed in the second phase hormonal drugs- gestagens (or). For pregnant women with low progesterone, these drugs are prescribed for up to 12 weeks. If the drugs are abruptly stopped, a miscarriage may occur.

In the first phase, the basal BT temperature under the influence of estrogens remains within 36.2-36.7 C. If the basal BT temperature in the first phase rises above the specified mark and if you see sharp jumps and rises on the graph, then most likely there is a lack of estrogen. In the second phase we see the same picture - ups and downs. On the graph, in the first phase, the basal temperature of the BT rises to 36.8 C, i.e. above normal. 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 such patients is sharply reduced. For treatment purposes, gynecologists prescribe hormone therapy. Having seen such a graph, there is no need to rush to draw conclusions - such a picture can also be observed in inflammatory diseases. gynecological diseases, when everything is in order with estrogens, for example, with inflammation of the appendages. The graph is presented below.

You see in this graph with sharp declines and rises that due to inflammatory process It is problematic to determine when ovulation occurred, since the basal temperature of the BT can increase both during inflammation and during ovulation. On the 9th day of the cycle, we see a rise, which can be mistakenly taken for an ovulatory rise, but this is most likely a sign of the onset of an inflammatory process. This basal temperature (BT) chart once again proves that you cannot 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 body temperature is lowered. If the temperature at the end of the previous cycle decreased, and then sharply rose to 37.0 with the beginning of menstruation and does not decrease, as can be seen on the graph, perhaps we are talking about a terrible disease - endometritis and you urgently need treatment from a gynecologist. But if you have a delay in your period and your basal BT temperature 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 in the graph 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:

Basal temperature (BT) charts with low or high temperature throughout the entire 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 by more than 10 days, while there is no pregnancy;
- if you observe a shortening of the second phase according to the graphs;
- if the graphs are anovulatory or the manifestations of ovulation are not clearly expressed on the graph;
- 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 charts are absolutely normal: ovulation occurs, both phases are full, but pregnancy does not occur within a year with regular unprotected sexual activity;
- 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 your own based on the obtained graphs. This can only be done by a qualified gynecologist, and then only after additional research.