HCG during pregnancy: the norm by week

2024 Author: Priscilla Miln | [email protected]. Last modified: 2023-12-16 00:21

Women in an interesting position or already established mothers know firsthand what the hCG hormone is. After all, it is "from him" that many learn that they are pregnant. Even when test strips can give false information, testing for hCG during pregnancy in the early stages gives a high probability. What is this indicator? What can you learn about pregnancy after an hCG test?

hCG - what kind of hormone

hCG (human chorionic gonadotropin) is also called the "pregnancy hormone". It belongs to the category of gonadotropic hormones, which, unlike the same follicle-stimulating hormones, have a completely different arrangement of amino acids.

HCG - differs from other hormones in the human body also in that it is formed in the shell of the embryo - the chorion, which is formed 5-6 days after the fertilized egg is attached to the uterine wall. It is the fertilized egg that synthesizes this hormone, so it is produced immediately after conception. Therefore, the time when hCG shows pregnancy varies from 3up to 7 days after fertilization. At the same time, ultrasound will not yet show the presence of a fetal egg.

That is why it is worth taking an hCG pregnancy test early in order to accurately confirm the expected condition. In addition, the indicators of the chorionic hormone throughout the entire period of bearing a child can show how the pregnancy proceeds: with deviations or in the norm. Therefore, it is worth conducting such a study several times during the entire period of pregnancy.

But the presence of hCG can also be observed in women who are not in position, as well as in males. The detection of this hormone in the body indicates serious he alth problems, in particular, the development of a hormone-producing tumor. In non-pregnant women, high levels of the "pregnancy hormone" indicate that the woman has recently had an abortion.

Role in the body

This substance promotes ovulation in a non-pregnant woman and also forms yellow bodies.

HCG during pregnancy plays an important role. In the first three months, gonadotropin stimulates the production of progesterone and estrogen - hormones that support the normal course of pregnancy. Gonadotropin supports the normal development of the fetal egg until it passes into the "fetus" stage and is unable to independently produce and stabilize its own hormonal levels.

If the developing fetus is male, then hCG stimulates the Leydig cells in it, which are responsible for the synthesistestosterone is a male hormone. In the first weeks of fetal development, gonadotropic hormone contributes to the formation of good immunity in him, and also significantly reduces the risk of rejection of the fetal egg by the mother's body.

Between weeks 2 and 5, the amount of hCG in the body doubles every two days. If a woman has more than one child, then the level of the hormone will be proportional to the number of developing fetuses.

Thus, we can say that hCG in the body of a pregnant woman is needed for:

• production of progesterone and estrogen;
• education and development of yellow bodies;
• reducing the risk of miscarriage by increasing the immunity of the fetus to the aggression of maternal immunity;
• stimulating the correct and uniform change in the physiology of the female body;
• stimulating the adrenal cortex and gonads of the fetus;
• sexual differentiation in male fetuses.

Based on the foregoing, it becomes obvious that the presented hormone is an important indicator in the body of both a pregnant woman and in the body of non-pregnant women, as well as men.

Definition of hCG

So, when passing such an analysis, blood is taken from a woman, but the indicator will be taken from the plasma. As a result, you can find out not only that there is a pregnancy, but also when the conception occurred, set the exact date.

It is possible to carry out the analysis already on the second day of the delay of critical days. And if the gestational age is already 6 days, then the test result will bepositive. An hCG study usually shows the correct result immediately, but if in doubt, you can re-analyze after 2 days.

To determine pregnancy, blood for hCG should be taken on an empty stomach, only then you can get "clean" data. And before taking it is necessary to notify the doctor about the possible use of hormonal drugs, as they can change the correct indicators.

HCG during pregnancy is prescribed not only in the first days or weeks after conception. Starting from the 4th month (14 weeks), this analysis is sent to identify abnormalities in the development of the fetus, since during this period the formation of its organs occurs.

The presence of the chorion hormone is determined by rapid tests familiar to many women. But in this case, not blood is applicable, but urine. It also has this element. However, the test strips show a positive result (if any) only on the 7th day after the delay, and the result of the blood for hCG is already a couple of days later. In addition, plasma levels of the hormone are twice as high as in urine.

Schedule an analysis if:

1. Must be diagnosed with pregnancy.
2. We need to check the dynamics of intrauterine development.
3. Determination of the anatomy of the fetus is necessary (detection of deviations in embryonic development).
4. An ectopic pregnancy should be ruled out.
5. An abortion was performed and it is necessary to make sure that the fetus is completely removed from the body.
6. The risk of possible miscarriage needs to be refuted.
7. There is a need to confirm or deny the presence of tumors in the body.

For men, such an analysis is prescribed if there is a suspicion of an ovarian tumor.

How is hCG tested during pregnancy?

It's worth starting with the fact that hCG is "built" from "alpha" and "beta" units. "Beta" units are the very landmarks that testify specifically to pregnancy, and it is they that doctors are looking for in a woman's blood.

Before delivery (4 hours) a woman must refuse food, for the purity of the result. You can take it at any time of the day, but, to confirm pregnancy, it is better to do it in the morning between 8 and 10 o'clock. A considerable number of doctors also recommend not to exercise a few days before the proposed analysis, also for a more reliable result.

To determine pregnancy, hCG is isolated from blood taken from a vein in the elbow area. After taking the material, the arm should immediately be bent and held for a while to avoid bruising.

So, the meaning of the analysis of gonadotropin during pregnancy:

1. 100% proof of conception, much more effective than test strips.
2. Determining the exact day of conception and, as a result, setting the exact date.
3. hCG will "tell" about whether the fetus is developing correctly.

The test for men and non-pregnant women is carried out in the same way as for pregnant women. But such a category of people must also be observedthe following rules:

1. For 24 hours before the proposed analysis, you must stop drinking alcohol, smoking, taking medications, physical activity.
2. A few hours before hCG, it is worth keeping calm, maintaining emotional balance, instead of eating and drinking, use only clean, non-carbonated water.
3. You should not go for an analysis if a medical examination, ultrasound, x-ray, massages, physiotherapy were previously carried out.
4. When re-passing the analysis, you must also follow all of the above rules. Only in this case can the purity of the result be achieved.

Women who have recently had childbirth or abortion are prescribed a re-analysis for hCG after 1.5 months in order to refute the development of tumor formations.

False analysis results

Even despite the fact that the analysis for hCG gives the maximum reliable information about the duration of pregnancy and the condition of the fetus, there are still cases when the information is false positive:

1. According to many gynecologists, oral contraceptives can affect hCG levels. Therefore, women taking such drugs, the tests give a positive result. But how reliable this belief of many doctors is not scientifically identified and proven.
2. After a recent birth or abortion, the amount of gonadotropin in a woman's body decreases within a week. After 2 months, the doctor prescribes an analysis for hCG. If the result shows a high level of thishormone, this indicates that a trophoblastic tumor is progressing in the body.

Therefore, if a woman is sure that she is not pregnant, and the results of hCG indicate the opposite, then she is prescribed a transvaginal ultrasound diagnosis. If the ultrasound also refutes the fact of the development of the embryo, then the woman is sent for other types of diagnostics to identify the disease.

What is the HCG rate during pregnancy?

As soon as fertilization occurs, the fetus begins to develop in the woman's body. From its shell - the chorion - gonadotropin begins to stand out. Elevated levels of this hormone indicate that pregnancy has occurred. The amount of gonadotropin begins to rise from the onset of the fetus, doubling every couple of days. It reaches its highest level in the period from 7 to 10 weeks. Then the indicator decreases slightly and remains until the second half of the 2nd trimester.

Human chorionic gonadotropin has its own measurement system - milli per milliliter (mIU/ml).

A reading over 25 mIU/mL is a sign of pregnancy.

Readings within 5 mIU/ml are the norm for pregnant women, as well as for men.

As soon as the level of hCG in a woman's blood reaches 1000-2000 mIU / ml, the doctor will be able to examine the fetal sac already on a transvaginal ultrasound.

Different pregnant women may have different levels of hCG. Therefore, it is not correct to draw conclusions from ultrasound data about the gestational age and date of conception until the hormone level approaches 2000.mIU/ml.

Deviations from the norm

The norm of hCG during pregnancy is an unstable indicator. Its change in one direction or another indicates violations in the development of the fetus, the appearance of complications.

Elevated levels of hCG during pregnancy can be a signal of one of the processes in the body of a pregnant woman:

1. Development of multiple embryos.
2. Complication of the gestational period or preeclampsia.
3. Severe toxicosis.

In addition, high levels of gonadotropin are characteristic of girls with diabetes.

Low levels of gonadotropin indicate the following processes:

1. In an ectopic pregnancy, hCG always deviates from the norm to a smaller side.
2. Missed pregnancy likely.
3. Delayed development of the fetus, its slow growth.
4. Overpregnancy.
5. Chronic placental insufficiency.
6. Self-abortion is not ruled out.

Also, deviations from the norm are possible if the doctor has incorrectly determined the gestational age. In this case, there may not be hCG in the woman’s blood at all. Or there may be a lot of it, which may indicate an ectopic development.

Mismatch between pregnancy dates established by doctors and hCG analysis findings

Common occurrence: the gestational age set by the gynecologist does not match what was revealed as a result of hCG tests. This is not a deviation in the development of the fetus, just the calculation that the doctor makes is different from the calculation for gonadotropin.

The deadline setdoctor is called an obstetrician, and it starts counting from the 1st day of the last menstruation. In fact, there is no pregnancy yet at this time, so the obstetric date will be 2 weeks behind.

The analysis of hCG during pregnancy counts the period directly from the moment of conception, therefore it gives more accurate indicators regarding the EDD (preliminary date of birth).

Factors affecting hCG rates

In addition to the fact of pregnancy, other factors can affect the level of gonadotropin. This applies to non-pregnant women and men. In this category of people, an increase in hCG can provoke:

• Tumors of the lungs, kidneys, testicles or ovaries, uterus, chorionic carcinoma;
• Hormonal drugs;
• For women, hCG may remain after a recent pregnancy or abortion.

In men, gonadotropin mainly indicates the development of a tumor.

In a developing fetus, gonadotropin levels may change if they are exposed to the following adverse conditions:

• Down Syndrome increases the levels of the hormone, while reducing the levels of other markers. Back in the last century, scientists found that the levels of this hormone in the body of a woman carrying a child with Down Syndrome are twice as high as those of a woman pregnant with a normal child. The indicators are similar to those for multiple gestation.
• Patau Syndrome and Edwards Syndrome stimulate a decrease in hCG and other markers.
• Turner's syndrome slows down hCG shifts, stabilizing it in more than oneindicator.

Elevated hormone provocateurs

During pregnancy, hCG changes week by week evenly in increments up to 14 weeks. Then the indicator stabilizes. But, it also happens that the level of gonadotropin in a pregnant woman rises. Reasons can be:

• Diabetes mellitus type 1 or 2.
• Intrauterine development of two or more embryos.
• Taking progestin drugs (hormones that promote conception and the normal course of pregnancy).
• Significant discrepancy between obstetric term and hCG results;
• Preeclampsia, early and severe toxicosis.
• Menopause can trigger the release of gonadotropin.
• Genetic abnormalities in the development of the fetus.
• Taking hCG medications for treatment.

With high levels of gonadotropin, a pregnant woman is prescribed a number of other tests that confirm one of the possible deviations. Then treatment is given, if possible.

Provocateurs of low hCG

Low levels of gonadotropin may indicate an incorrectly established gestational age, when the true indicators of the amount of the hormone do not correspond to the term.

But, most often, a decrease in the "hormone of pregnancy" indicates serious violations in the development of the fetus. These factors include threatened miscarriage, ectopic pregnancy, delayed development, etc.

HCG indicator tables

For better orientation in terms of gonadotropin, it is worth bringing a table withhCG levels by week of pregnancy.

HCG levels by week

Week	Level
3	5-50
4	5-426
5	18-7340
6	1080-56500
7-8	7650-229000
9-12	25700-288000
13-16	13300-254000
17-24	4060-165400
25-40	3640-117000

HCG norm by week of pregnancy

Weeks	HCG levels (mIU/ml)
1-2	25-156
2-3	101-4870
3-4	1110-31500
4-5	2560-82300
5-6	23100-151000
6-7	27300-233000
7-11	20900-291000
11-16	6140-103000
16-21	4720-80100
21-39	2700-78100

The figures shown are only a guide, as each pregnant woman may experience an increase in different ways.