The birth of the long-awaited baby is preceded by nine months of longing. And in order to know the exact time of birth of the baby, it is necessary to establish the current gestational age.
As a rule, the absence of menstruation is the first sign of pregnancy, forcing a woman to turn to all kinds of ways to clarify her condition. You can do this at home with the help of a pharmacy test or by resorting to folk remedies using iodine or baking soda.
Moreover, today you can determine pregnancy in the early stages - before the delay of menstruation. All methods will be discussed in more detail in this article.
Establishing the presence of pregnancy in folk ways
In a small portion of urine collected after awakening, you need to add a couple of drops of iodine or a spoonful of soda. Having estimated the result of the chemical interaction of substances, we can come to the following conclusions:
- You are pregnant if soda does not react with urine, but simply precipitates to the bottom of the dishes.
- You are pregnant if iodine remains on the surface of the urine without dissolving in it.
The directly opposite processes of the interaction of these substances with urine (a violent reaction with soda or dissolution of iodine) indicate the absence of pregnancy.
True, such methods are, rather, emergency methods of establishing the fact of pregnancy, rather than its exact duration. However, these methods are effective only in the early term (less than nine weeks), therefore, a positive result will indicate your approximate term (first trimester).
The method used by gynecologists
Not all methods offered by medicine guarantee an accurate result. For example, the methods used by gynecologists to determine the gestational age are designed for a woman to consult a woman earlier (before the first trimester of pregnancy, that is, the thirteenth week).
Specialists of the antenatal clinic use the traditional medical method.
Based on changes in the uterus, an experienced specialist can accurately indicate the period. The unit of account is the length of the uterus at the time of examination, which corresponds to the number of weeks of pregnancy. For example, a length of thirty centimeters would correspond to thirty weeks.
The problem is that starting from the third month it is more difficult to determine the gestational age by weeks in this way. Since up to a certain point the embryo develops equally in different women. At later dates, the development of the unborn child can occur individually, depending on the genetic characteristics of the mother's body, as well as the presence of certain diseases.
To more accurately determine the gestational age by weeks, a gynecologist using a tazomer or a centimeter tape measures the height of the uterine fundus in relation to the womb of the woman, as well as the abdominal circumference of the future mother. To avoid errors, measurements are taken with an empty bladder.
In a later period of gestation, the priority way to clarify data on the term is to control the volume of the abdomen of a pregnant woman. In particular, a tazomer is used to determine the size of the fetus. The doctor sets the body parts of the baby to the touch, and then takes measurements. In this case, one part of the device (tazomer) is located at the bottom of the head, the other - in the area of the fundus of the uterus, where the baby’s ass is usually palpated.
It is believed that the value obtained as a result of such a measurement is equal to half the length of the baby. The value obtained during the measurement must be multiplied by two and subtracted about five centimeters. The final result of the calculation, the gynecologist divides into five and thus determines the current gestational age in months.
The traditional method of determining the term is quite effective until the end of the first trimester of pregnancy, but at a later date it can have large errors. Therefore, along with medical methods, other methods for determining the term are widely used.
Obstetric method for calculating gestational age
In addition to examining and establishing the size of the uterus, the specialist is repelled from the date of the start of the last menstruation. You can also determine the gestational age according to your monthly periods by yourself: by the first day, when a woman begins menstruating, it is necessary to add 280 days (forty weeks).
Such a calculation is a rough determination of the term, as it is based not on the very moment of conception, but on the approximate establishment of the period, based on the periodicity of the patient’s monthly cycle.
In utero, the fetus fully develops within thirty-seven to forty-two weeks, depending on the individual characteristics of the course of pregnancy. Thus, the exact period may diverge from obstetric. And the period of discrepancy reaches about two weeks, since on average it is precisely two weeks that separate the moment of the beginning of the monthly cycle from the expected moment of ovulation (the most favorable time for conception).
Determining the gestational age by menstruation is considered the most simple and affordable way. It is enough to know the date of the first day of the last menstruation. By counting the number of past weeks from this date, you yourself will determine your current term.
Calculation according to the Negel formula
A simple method for determining the gestational age for women with a regular monthly cycle. The calculation is carried out from the start date of the menstrual cycle according to the following formula:
the start date of the last menstruation is three months + seven days = date of birth.
Calculation of the term at the time of fertilization of the egg
This method requires more accurate information. In particular, to determine the gestational age by the date of conception, it is necessary to know the date of ovulation. This is the most favorable time for fertilization. If pregnancy was previously planned and the woman specifically calculated the most favorable period for conception, it is not difficult to establish the exact date by adding to the ovulation date the number of weeks that have passed since her moment.
With a regular monthly cycle, it is not difficult to calculate the moment of conception. Using the average duration of the normal twenty-eight-day cycle, we establish the approximate date of ovulation. It will occur on approximately the fourteenth day, that is, exactly at the middle of the cycle. For those who do not know how to determine the exact gestational age on their own, this method may well be suitable. But with a non-standard cycle duration in a woman, this option is unlikely to give exact values.
Research method
If it is not possible to determine the time by the above methods, this can be done by ultrasound (ultrasound), which is carried out only by a specialist with the help of special equipment. Many say that this is the only way to determine the exact gestational age. But here there are some nuances. The most accurate result of the study is possible only in the first thirteen weeks of pregnancy, when the development of the embryo in different women, as a rule, proceeds standardly. However, a planned study is usually prescribed in the second trimester, therefore, in the early stages, ultrasound can be done independently for a fee. This is one of the most popular ways to determine the gestational age.
During the procedure, the specialist determines the size of the fetal egg and the embryo itself. Based on the measurements obtained, the current gestational age is established. As a rule, the period established by a specialist coincides with the obstetric one (provided that the woman had a regular monthly cycle before pregnancy).
Fetal movement
The first signs of fetal movement are an alternative method to determine the gestational age. Can be used in the second trimester. The feeling of fetal movement during normal pregnancy first occurs in the twentieth week of pregnancy (or in the fifth month). Multiparous mothers have earlier signs of movement, for example, at the eighteenth week.
This method cannot be considered reliable in view of the fact that different women begin to feel their baby in completely different periods of pregnancy: someone a little earlier than the generally accepted term, someone, on the contrary, later. In addition, some primiparous mothers often confuse fetal movements with processes in the intestine.
Pregnancy test - how long does it determine?
This is the most popular way among modern women. Many expectant mothers are interested in the question of how long a pregnancy test determines its presence. Judging by the instructions of most of them, it is advisable to do it starting from the first day of the delay. In pharmacies today you can find electronic rapid tests, the manufacturers of which promise to indicate not only the fact of pregnancy, but also its duration. Their action is based on the hCG level, and it does not always correspond to the required indicators.
Determination of the term for the hCG indicator
Almost from the moment of conception, chorionic gonadotropin (hCG) begins to be actively produced in the mother's body. Pregnancy hormone performs the function of protecting the embryo. Each week of pregnancy corresponds to an allowable level of the hormone, according to which it is possible not only to clarify the term, but also to identify deviations in the development of the fetus, as well as pathology during pregnancy. Particularly intensively, chorionic gonadotropin is produced in the early stages, and starting from the twelfth week of pregnancy, its level in the blood of a pregnant woman decreases. The maximum values of hCG are observed after two months after conception.
Experts say that this is not the most reliable way to determine the gestational age. The problem is that an obtained hCG level indicator, depending on various factors, can have a rather large spread. The hormone values vary (may be reduced or too high in comparison with the norm) in the presence of pathologies, as well as in the presence of a woman with multiple pregnancy.