Biochemical Pregnancy, also known as Chemical Pregnancy, is a medical term to describe the early abortion that occurs before the fetus before the fifth week of pregnancy.
In simple terms, biochemical pregnancy is essentially an ultra -early abortion.
We know that, compared to the "happy pulse" of traditional Chinese medicine, modern medicine has long developed a reliable method for diagnosis of early pregnancy, which is the pregnancy test of HCG testing.
HCG, also known as velvet fur membrane, is a hormone secreted by the placenta after the fertilized eggs (implanted in the endometrium).
After the female ovulation, if the egg is combined with sperm, the embryo will be implanted in the endometrium after about 1 week.At this time, the placenta began to produce HCG and entered the blood.
We can detect it through pregnancy tests, saying that the pregnancy test is positive, showing that it may be pregnant.In order to detect convenience, tests are often tested by testing HCG in urine.
Generally, embryo implants occur after an average of 9 days (6 ~ 12 days) after ovulation, or about 5 days after menstrual delay.HCG levels can be detected in the blood 2 to 3 days after implantation, and 3-4 days after implantation can be detected in urine.
That is to say, the urine pregnancy test is expected to be positive for about 10 to 14 days in menstruation.The earliest can even be earlier on the seventh day in advance.
However, we know that the lower the large animal reproductive efficiency, the lower the humans are one of them.
Fertilization, embryonic formation, or even implantation does not mean that pregnancy can be successful.
Instead, there is a great chance that embryos or fetal loss occur at all stages of pregnancy.Among them, the abortion occurred before 22 weeks of pregnancy.It occurred 12 weeks before it was called early abortion.It happened 5 weeks ago, and it was called an early abortion.
What is the concept of 5 weeks of pregnancy?Although the embryo has been implanted in the endometrium, the placenta has begun to produce HCG and detected through pregnancy tests, that is, positive pregnancy test.
However, at this time, the embryo sac is not enough to see through ultrasonic examination that the ultrasonic heartbeat can not be detected (it takes 6 to 7 weeks).
In other words, at this stage, in addition to the biochemical test of the pregnancy test, pregnancy cannot be determined by other means.Therefore, pregnancy at this stage is called biochemical pregnancy.
Correspondingly, after 6 to 7 weeks, the fetal heart can be seen in ultrasound examination, called clinical pregnancy.
Although some embryos have been implanted in the endometrium, they have stopped developing due to various reasons, and there are no surviving embryos.After death, an ultra -early abortion occurred from the endometrium.
These pregnancy, after the early stages of pregnancy test, not only does not rise rapidly with the time (early pregnancy, the HCG level is usually doubled every 48 ~ 72 hours), but it will decline.It shows that the embryo has miscarriage after early implantation.In essence, there is no real implantation and no living embryo.The process of this phenomenon is the biochemical pregnancy of the subject consultation.
Biochemical pregnancy is usually discovered in women who do IVF, because embryos will be closely observed after embryonic implantation.
The biochemical pregnancy of the general population is usually not discovered and there are no symptoms.The only "abnormal" is that the next menstruation may be postponed for several days.
Only when women are very expected to be pregnant and women who have conducted pregnancy tests every day after a monthly period can find biochemical pregnancy.
There are many possible reasons, and it is usually difficult to determine.
The most common of these is the abnormalities of embryo chromosomes. This embryo has been destined to survive from the beginning. Abortion is a natural choice for survival of the fittest.
Other reasons can include insufficient endometrium, low hormone levels, luteal stabilization, infection or other unknown reasons.
As mentioned above, humans are one of the most efficient large animals, and the high outflow rate is one of the specific reflection.
According to the statistics of the American Society of Obstetrics and Gynecology, about 10 ~ 25%of clinical confirmation of pregnancy ended in abortion, and 50 ~ 75%of them belonged to biochemical pregnancy.
Since a large part of biochemical abortion is not tested, this 50 ~ 75%is far from all of biochemical abortion.
According to a study from the University of Oxford, the natural abortion rate of human beings can be as high as two -thirds of all pregnancy.Scientists are using high -sensitive urine HCG detection methods to prove that about 30%of fertilized eggs withered before (real). Although 30%of them can be implanted, they cannot develop living embryos. Ultrasonic examination can only see an empty embryo sac., Can’t see fetal hearts.These two situations usually occur 6 weeks ago, collectively known as biochemical abortion or preclinical abortion, that is, biochemical or chemical pregnancy.
About 10%of those who develop into embryos have miscarriage at all stages of pregnancy for various reasons. In the end, only about one -third of the fertilized eggs can develop into living babies.
The scientist’s image uses the iceberg map as follows. The clinical abortion and live production parts are only 40%floating above the water.
It can be seen that the so -called biochemical pregnancy is a very common phenomenon.
Moreover, in this study, scientists found that these ultra -early abortion embryo malformation rates were as high as 80%, and the abnormal rate of chromosome nucleus was as high as 75%.In other words, the elimination was originally those "crooked melon jujube".In advanced abortion, even habitual abortion, the nuclear abnormal rate of abortion fetus is only 3-6%.
It shows that ultra -early abortion is a natural choice of natural selection of the fittest, which is not groundless.
In addition, research has also found that the occurrence of biochemical pregnancy will not have any impact on future pregnancy, so there is no need to worry about it at all.
Unless, if a biochemical pregnancy occurs many times in a row, you need to pay attention and need to be checked.