Produced: Popular Science China
Supervision: Computer Network Center of the Chinese Academy of Sciences
In recent years, a test strip that is said to be able to do fetal gender prediction has been circulated on the Internet.The principle is to perform fetal gender predictions based on the pH of pregnant women’s urine.Specifically, the urine of more than 6 weeks of pregnancy and the first urine in the morning is injected into the test cup. If the urine of the pregnant woman’s urine is greater than 7, it is weakly alkaline, and the boy is pregnant;So the girl may be pregnant.
So, is this test paper real?Can pregnant women urine and alkali really predict the gender of the fetus?In other words, can the fetus determine the pH of the pregnant mother’s urine?
The answers are negative.
Don’t take it seriously, it’s just a test of "testing and playing"
In fact, this test is not much better than throwing coins.This is just an entertainment test. The corresponding test is also "for fun" in the United States.
The co -sponsor of the kit Intelligender company, Robica Griffin, said we did not make any promises to the test accuracy in product packaging. It is also recommended that consumers do not make any decisions based on the test results.In fact, customers test it only for fun."We are very surprised, and there are customers who prepare boys or girl clothes based on the test results."
Figure 1. Intelligender in its manual clearly marked the test as "A Fun Pro-BIRTH Experience" (testing)
After spreading to the country, Chinese merchants claim that "can accurately predict that men and women, the accuracy rate reaches 90%."Not to mention that it is just "testing and playing", even if the corresponding kit can get accurate test results, this type of kit is illegal in production, sales, and use in domestic production, sales, and use.my country’s population and family planning laws, maternal and child health laws, and family planning regulations formulated by provinces and cities all stipulate that "it is strictly forbidden to discriminate the sexual identification of fetal needs for non -medical needs."
What are the urine components?
As we all know, urine is one of the products of human metabolism.95%-97%of human urine components are water, and the remaining solid components are mainly composed of uric acid, urea, water, inorganic salt, hormones, etc.The human body needs to consume about 2000ml of water every day. The water intake of food is about 1000-1200ml of water in three meals.Most of the water discharge through urine, sweat, and breathing.
Figure 2. A routine urine test report
The normally about 4.5-8.0 in human urine is about 4.5-8.0.Normal people’s urine is weakly acidic and can also be neutral or weakly alkaline.The acidity of urine is mainly affected by diet, metabolic status, and medication.
In the hospital, urine testing is called urine routine. The indicators on the test report include: pH (pH), urine gravity (SG), urine biliary (URO), hidden blood (BLO), white blood cells (WBC), urine protein (urine protein (urine protein (urinary protein)PRO), GLU (GLU), bilirubin (BIL), ketone body (KET), urine red blood cells (RBC), urine color (GOL).The reference value is 5.5-7.5, that is, weak acid to weak alkali.
For certain metabolic diseases, the acid and alkali of urine will deviate from the normal range.For example, increased pH is common in frequent vomiting, respiratory alkali poisoning, etc.; Reduced acid and alkali is common in acidosis, diabetes, chronic glomerular nephritis.
The metabolic load of pregnant women is heavier than normal people.During pregnancy, the mother and fetal metabolic waste need to be discharged: the glomerular filtration rate increases by about 50%, the blood flow of the kidney increases by about 75%, the kidney burden is worse;; Some nutrients, such as glucose, amino acids, and water -soluble vitamins increase; the amount of urinary discharge of glucose can increase by more than 10 times, but this should be different from real diabetes; the average daily discharge of amino acids is about 2 grams; the discharge of folic acid is excretedIt is twice as high as non-pregnancy, about 10-15 micrograms / day.
When pregnant women suffer from hypertension and kidney disease, the protein content in the urine will be higher. In severe cases, the urine protein in urine in 24 hours can even reach ≥5.0g, which is called pregnant women’s proteinuria.
During the early pregnancy, the "chorionic gonad hormone" in urine testing and blood can determine whether women are pregnant, but the choric membrane has nothing to do with the gender of the fetus.
Expert Professor Xu Yang believes that the differences between the hormones secreted by the male and female fetuses in the mother’s body are extremely subtle. In addition to the interference of the maternal hormone, it is difficult to accurately identify the gender of the fetus by detecting the level of hormones in the urine.At the same time, this method does not have sufficient support for evidence -based medicine.You know, whether the sperm that determines the sex of the fetus is X chromosomes or Y chromosomes.
There is indeed a way to accurately detect the gender of the fetus
At present, there are three methods in medicine to identify the gender of the fetus in the abdomen.However, in addition to the corresponding indications, doctors will not inform the fetus in violation of regulations.
The first is the B -ultrasound. The accuracy of B -ultrasound depends on the experience of the doctor and the posture of the fetus.The second is to perform the amniocentesis method in the medium term, and the amniotic fluid cell analysis is carried out after training amniotic fluid cells.This test may cause the risk of amniotic fluid embolism, infection, bleeding, injury to the fetus.Therefore, if it is not for medical needs, do not detect it.Third, the third trimester can also be identified by chromosomal cord blood.The chromosome nucleus type is analyzed through this method, and the accuracy is high.
The gender identification of the fetus with a small number of cases in China is mainly to identify accompaniment genetic diseases.In addition, the sexual appraisal of the fetus required for medicine shall collectively review the expert groups with more than three implementation institutions.At present, human beings have more than 190 accompaniment and hidden diseases, such as albinism, color blindness, nephreal diaper and urine, etc., and more than 10 accompaniment genetic diseases, such as pheasant diseases, hereditary chronic nephritis.Most of the hidden inheritance is the mother -in -law, and the explicit inheritance is the father of the father.
Figure 3. Pay attention to the appropriate amount of water during pregnancy
Fetal gender has nothing to do with the urine acidity and alkali of the pregnant mother
Therefore, under normal physiological conditions, the acid and alkali of various tissues, organs and blood of the human body are relatively stable, and there is no "acidic constitution" and "alkaline constitution" in medicine.The acid -base balance of the human body is jointly controlled by multiple organs, and will not become "alkaline" or "acid" constitution because of diet or pregnancy.Therefore, the gender of the fetus has nothing to do with the pH of the pregnant mother’s urine.
Each baby is unique, and pregnant mothers should not pay too much attention to the gender of the fetus.Usually, what pregnant mothers need to do well in health care, pay attention to diet, drink an appropriate amount of water, and do not urinate.
In a word, the pH of the urine is not worthy of excessive attention. It is only a small test that the fetal gender is only "measured" by detecting the acidity and alkali.
"Popular Science China" is a scientific authoritative brand with information technology with information technology with information technology.
This article is created by the fusion of popular science China. Please indicate the source for reprinting.