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What is the basal temperature before menstruation?
Last reviewed: 23.04.2024
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Basal temperature before menstruation can give answers to a woman's condition and her hormonal activity. Therefore, to plan their lives, every intelligent woman must understand the phases of its cycle and be able to control all processes.
Regulation of the cycle in women and basal temperature
Any woman can be useful to create her menstrual calendar or a special diagram of her cycle. In doing so, you can learn your body, find out what is normal for you, and have a benefit for your own health. Your menstrual cycle can in principle be divided into phases: the preovulatory sterile phase, the fertile phase and the post-vascular sterile phase. You can determine at what stage you are, observing three basic birth rates: basal temperature, cervical fluid and cervical position.
The menstrual cycle is under the direct influence of estrogen and progesterone, and the body reports on the status of these hormones daily. The estrogen dominates in the first part of the cycle; progesterone dominates the latter. Another hormone called luteinizing hormone (LH) is a catalyst that stimulates the ovary to release the egg. Ovulation (egg release) occurs once per cycle. During ovulation, one or more eggs are excreted. The egg can be active for 12-24 hours. All these processes affect the basal temperature.
Women who have natural menstrual cycles have a two-phase basal temperature structure. The first phase of your cycle has low temperatures, and the second phase of your cycle has higher temperatures.
The first phase is called the follicular phase. This phase begins on the first day of your period every cycle and ends when you ovulate. After ovulation, the luteal phase. After ovulation, the yellow body (the remnants of the follicle that releases the egg in ovulation) produces a heat-inducing hormone, progesterone. Progesterone, produced by the yellow membrane during your luteal phase, increases your body's basic temperature. The main reproductive function of progesterone in the luteal phase is to cause changes that prepare the lining of the uterus for the implantation of a fertilized egg. However, progesterone also leads to an increase in body temperature after rest after ovulation. Because progesterone is only secreted at high levels after ovulation, it is possible to determine ovulation during the day before the temperature rises when the temperatures are plotted. The temperature range can vary from woman to woman, because each person is unique. If there is no pregnancy, your temperature will remain elevated for 10-16 days until the yellow body regresses. At this time, if there is no pregnancy, the level of progesterone drops sharply, and you get menstruation. Your temperature usually falls and at this time, although it is not uncommon to have unstable or high temperatures during your period of menstruation.
But it should be borne in mind that the basal temperature is the temperature of your body at rest, unchanged by other factors. It can be used to reliably confirm ovulation, since progesterone, which is produced only during the luteal phase, increases your body's basic temperature.
Characteristics of basal temperature
Measuring the temperature of your body on a regular basis can help you find out when will ovulate. Usually there is a drop in temperature just before ovulation and a sudden increase after that.
What is the basal body temperature? This is the lowest value of body temperature when it is measured in the morning after rest. This is the baseline value, which is then used to compare any rise or fall during each month. For the values to be effective, a woman needs to measure her temperature before she even gets out of bed and if she sleeps for at least four hours, and preferably more. It is very important to measure its temperature before eating, drinking or going to the bathroom and before any sexual activity - all this raises the heart rate and, in turn, the body temperature from the original level.
How to measure? A digital thermometer can be easier to use than a mercury thermometer, and it's important to have a thermometer that measures Celsius, not Fahrenheit. Specially developed basic body temperature thermometers are available in pharmacies. In terms of accuracy (which is important when measuring the basal body temperature), it is worth buying a new thermometer. Basic thermometers give more accurate temperature readings than standard digital thermometers. When using a basic thermometer, it is important to follow the manufacturer's instructions. Each design is slightly different and to ensure accuracy it is important to follow the steps in the correct use.
The thermometer should be placed under the tongue and left there until it beeps. If you are using a mercury thermometer, it must be left for three minutes to obtain an accurate reading.
When to start measuring your body's basic temperature? The first morning of the menstrual cycle, as this indicates the beginning of each cycle. It is important to be sure that the value is accurate.
How correctly to note a basal temperature? Take the temperature value obtained and mark X in the field where the date and temperature intersect. Connect each point to the line and see if there is a change in the month when the line goes up or down. Over time, you will probably see a sample of degrees that reflects your ovulation patterns.
For each new month and every menstrual cycle, it is important to start a new chart. For each day of the month when you had sexual intercourse, circle the point on the appropriate day or place a small symbol similar to an asterisk (*) in the field at the bottom of the diagram.
Remember that this is not so much an individual measurement of temperature, which is important, but also a picture of the change between the first and second halves of the cycle. As a rule, in the first half (before ovulation) there is a lower temperature record and a higher "splash" (after ovulation) in the second half.
What changes in basal temperature during the month? During the regular 28-day menstrual cycle, the normal body temperature is around 36.5 ° C. Just before ovulation, your temperature is likely to drop to 36.2 ° C. This is normal for this to happen during the 13-14 days of the cycle. Then, just like you are ovulating, your temperature will increase, and it will grow until it rises to 37 ° C, where it will remain until the moment of menstruation.
What should be the basal temperature before menstruation? The norm of this value is individual. But on average this figure reaches 37, and then gradually decreases. How many days before the month does the basal temperature drop? As a rule, for 3-4 days there may be a slight decrease in temperature, but not lower than 36.8. Basal temperature a day before the monthly drops a little more to 36.5, and then before ovulation reaches the lowest figures. Thus, the basal temperature chart before the monthly temperature has a constant value and it is slightly lower than after ovulation. Basal temperature before the monthly day and evening may differ, but these values are not significant.
But the basal temperature can be 36, 37, 38 before the monthly, which may be an individual feature or may reflect the presence of a concomitant condition in a woman.
Therefore, as a rule, women need to determine the temperature of the main basal body for three or more months before they see a predictable picture. It takes time to strengthen the confidence in the ability to predict ovulation or menstruation through changes in temperature and other body changes.
Factors that can disrupt the morning temperature: fever, alcohol consumption per night, less than three consecutive hours of sleep before measuring the temperature, thyroid status.
How much is the change in basal body temperature accurate? Preservation of the body's basic temperature is not an accurate predictor of ovulation. In many ways, it is more useful as a tool for measuring ovulation after it has occurred, rather than earlier. Saving the record, and then interpreting the picture of temperature and fall increase will help you to know when your most fertile time period is most likely. But remember that this is not a guarantee that you will conceive, and there are several factors that need to be leveled before conception. Not all women increase their temperature when they are ovulating and, although it is considered normal, this is not a consistent picture among all women.
An increase and decrease in basal temperature before menstruation may have several causes. What is the extremely low basal body temperature? Usually there is a small difference between the low temperature phase and the high temperature phase: this difference is 0.3 to 0.5 ℃, and the basal temperature level is usually in the range of 36 to 37 ℃.
If you have less than 36.5 ℃ even during the high temperature phase, this means that you have a low basal body temperature.
Low basal body temperature can be caused by many causes, but one of the reasons is associated with changes in the level of hormones. Since female hormones affect temperature, changes in levels of secreted hormones, in addition to stress, accumulated fatigue or lack of sleep, changes in the diet can lead to a low body temperature. In addition, an unhealthy diet that does not hold the body warm enough or has food that can reduce your level of BBT and thus worsens blood circulation is a factor that can contribute to low basal body temperature. Even if you are well adapted to the problems and continue to maintain a healthy lifestyle, an increased level of hormone secretion can lead to your thyroid gland or your reproductive organs being slower to function and will contribute to low basal body temperature. It is recommended that you visit a doctor and check yourself if you have a constantly low basal body temperature for a period of 3 to 4 weeks.
Low basal body temperature can be, in some way, corrected by changing the way of life. Having a regular schedule that you follow with sufficient sleep and a balanced diet can help regulate the secretion of hormones and increase your temperature. Find ways to help yourself cope with stress and do not let it build up, because stress can affect hormonal secretions.
The increase in basal temperature can be against the background of illness and hyperthermia of the system, so this fact needs to be taken into account in such changes.
Basal temperature before monthly can vary, which allows you to plan your affairs with an irregular cycle. But you can evaluate the basal temperature only after a careful analysis of the temperature charts that are built after your observations for at least three months in a row.