The basis of the basal temperature method is the indirect effect of progesterone on the thermal receptors of the hypothalamus, which causes an increase in basal temperature in the second phase of the menstrual cycle. Scientifically proven that under the influence of progesterone the rectal temperature rises, under the influence of estrogens - decreases. If we talk about the interpretation of these data for setting the day of ovulation, doctors recognize that the day of ovulation is the day "before the beginning of the growth of temperature indicators." Basal temperature before menstruation can not be considered a reliable method of determining the time of ovulation (the correlation between changes in ovaries and basal temperature changes is only 40%). The technique works well for "home" testing: it helps in planning pregnancy with a confirmed absence of menstrual cycle pathologies.
What is ovulation?
Ovulation is the stage of the menstrual cycle, the exit of a mature egg into the abdominal cavity. In women who are capable of conceiving, ovulation occurs every 21-35 days. Periodicity is supervised by follicular hormone of the ovary and gonadotropic hormones of the pituitary gland. Ovulation contributes to the thinning of ovarian tissue and the accumulation of follicular fluid. Constant for each woman the rhythm of ovulation changes after 40 years, after abortion and childbirth. In the climacteric and with the onset of pregnancy, ovulation ceases. Subjective / objective symptoms of ovulation: pulling pains in the lower abdomen, lowering of BT on the day of ovulation and its rise to the next, increasing the amount of vaginal mucus, increasing the level of progesterone in the blood. Failure of ovulation can be triggered by inflammation of the genitals, stress, systemic diseases, dysfunction of the thyroid gland / adrenal cortex. Anovulation is manifested by uterine bleeding, scanty menstruation, amenorrhoea.
Signs of fertility (the ability to conceive)
At the beginning of the cycle, the opening of the cervix closes the plug, consisting of thick mucus. Maturation of the egg causes a sharp increase in the concentration of estrogens, under the influence of which the glands of the cervix begin to actively produce mucus. At the first stage, the buccal mucus is viscous, on the second one it is slippery and transparent - this is manifested by a sensation of moisture on the threshold of the vagina. Fetal mucus resembles a raw egg white, it is rich in the nutrients needed for sperm to move into the uterus. Conception is possible, if there is slime. Impossible if it is not. Another important sign of fertility is a change in the position and consistency of the cervix. Before ovulation, it is firm, dry, lowered down the vagina. In the ovulatory period, the cervix becomes moist, soft, raised to the top.
What helps to determine basal temperature:
- presence of diseases of the female reproductive system;
- whether ovulation has come;
- "Dangerous" (high probability of pregnancy) and "safe" (pregnancy is impossible) days;
- To find out whether a conception occurred in the case of unusual menstruation or its delay;
- time of onset of menstruation;
- presence of any abnormal deviations in the cycle.
Basal temperature is the temperature of the blood of an inactive organism. It should be measured in the rectum, because there it varies in cycles due to the function of the ovaries. Due to the peculiarities of their blood supply, cyclical fluctuations are intensified exclusively rectally. The definition of ovulation is based on the measurement of the temperature of the blood in the vein of the testicle, so you can not record the temperature in the vagina or oral cavity - this is a useless thing.
Normal basal temperature before monthly: chart
Normally, the BT schedule looks like a "flying seagull": in the first half the temperature is below 37.0 degrees, in the second - above 37.0 degrees. The menstruation lasts 5 days, the decrease of BT before the monthly takes 4 days, the rise in the middle of the cycle is 3 days, the egg ripens on day 15, the "dangerous" days for conception are 9-21, the difference between the numbers of the second and the first phase is more than 0.4 degrees .
The ideal schedule for a cycle of a woman capable of fertilization:
- from the first day of the menstrual cycle and until the end of the monthly basal temperature decreases from 37.0 degrees to 36.2-36.6 degrees;
- until the middle of the cycle, BT is in the range of 36.2-36.6 degrees;
- in some cases, before ovulation, due to the onset of the luteinizing hormone peak, BT decreases by 0.1 degree;
- the second phase of the cycle is characterized by temperature indices of 37.0-37.4 degrees (insignificant fluctuations are permissible);
- 14 days before the next month, ovulation occurs and BT rises to 37.3 degrees;
- 2 days before the monthly basal temperature gradually decreases and by the beginning of menstruation reaches 36.7-36.8 degrees;
- the discrepancy between the average BT index of the first and second phases should be 0.4-0.5 degrees.
Basic rules for measuring basal temperature:
- It is desirable to measure BT at 6-7 in the morning, at one time (plus / minus an hour);
- use a mercury thermometer, the electronic thermometer distorts the readings;
- waking up, without sitting down, without getting out of bed, you should enter the thermometer into the anus at a depth of 4-4.5 centimeters;
- when plotting the schedule, it is recommended to carefully fix the factors that can affect the basal temperature: a disease with temperature fluctuations, the use of alcoholic beverages, the use of sleeping pills, and insufficient sleep. It is very important to observe changes in cervical mucus and menstrual bleeding.
If the basal temperature before the monthly increases - the causes:
- 36.9 in the first phase of the cycle. The reason lies in the low content of estrogen, the incorrect operation of the ovaries. Lack of female sex hormones - the egg does not ripen - the woman is barren in this cycle;
- 37,1 / 37,2 against the background of delay in menstruation. Probable sign of pregnancy;
- 37.3 before the monthly. Indicates a transferred infectious disease or inflammation focus;
- BT stubbornly holds at the level of 37.1-37.5. Suspicious symptom - there is a high probability of ectopic pregnancy.
If the basal temperature before the monthly decreases - the causes:
- in the second phase, the basal temperature falls (decreases below 37.0 degrees) 1-2 times. This is a clear sign of the death of the egg;
- a decrease in BT before menstruation lasts 3 or more days. The situation points to a "weak" egg, which it did not work to impregnate;
- against the background of a delay in menstruation, the basal temperature drops below 37.0 degrees. This suggests dysfunction of the ovaries.
Variants of menstrual cycle phases on the basis of BT schedules
- The high temperature indices (36.9 and 37.5) in both phases with a difference of 0.4 degrees are the hyperthermal state, which is an individual feature.
- Low basal temperature (36.1 and 36.5) in both phases, while maintaining a divergence of 0.4 degrees, is normal.
- The usual temperature in the second phase (37.1-37.4), high (36.8) - in the first. A testimony of the lack of estrogen, which must be taken if pregnancy is planned in the near future.
- Basal temperature of the first phase within the norm (36,4-36,5), the second - below the norm (36,8-36,9). Symptom of deficiency of the yellow body, which is filled with progesterone.
When you need a visit to the gynecologist after measuring the basal temperature:
- basal temperature charts ovulate is absent during 3-4 menstrual cycles;
- against a background of several cycles with clear ovulation and regular sexual life, pregnancy does not occur;
- the presence of cycles longer than 35 days, shorter than 21 days;
- high BT more than 18 days in the second phase in the absence of pregnancy;
- elevated / low basal temperature throughout the menstrual cycle.
Basal temperature before menstruation helps doctors to identify gynecological problems, put the right diagnosis, prescribe the right treatment. To date, the BT method is the most affordable and cheap, but also the most unreliable. Do not worry because of missing or extra degree on the graph of basal temperature, it can not be used for diagnosis and therapy. At any doubts it is necessary to address to the gynecologist, instead of to be engaged in a selftreatment.