HCG during early pregnancy

Early hCG during pregnancy can be an important diagnostic sign of not only the pregnancy itself, but also its course. Understanding the nature of this hormone and determining its level can be important for diagnosing the course of pregnancy and the condition of the fetus.

What is hCG?

HCG transcript allows to define this concept as human chorionic gonadotropic hormone. This is one of the hormones that is an indicator of endocrine function in women outside of pregnancy and during pregnancy.

HCG is a classic pregnancy hormone that is produced by the placenta. When you test at home with a pregnancy test, you actually check for hCG. If hCG is present, the pregnancy test will be positive, and this means that you are pregnant if there is no false positive pregnancy test.

Human chorionic gonadotropin is a placental hormone, which is first secreted by cells (syncytiotrophoblasts) from the implanting germ for a week, supporting the ovarian body membrane, which, in turn, supports the endometrial lining and, therefore, supports pregnancy. HCG enters the blood shortly after implantation and is detected by pregnancy tests. HCG begins to be produced by the placenta immediately after implantation. This happens about a week after fertilization and ovulation, when the implants of the embryo and placenta are attached to the uterine lining.

Implantation occurs on average 9 days after ovulation (range 6-12 days), or about 5 days before the missed period. Levels of hCG are detected in the blood for 2-3 days, and in the urine 3-4 days after implantation. It is expected that the urine pregnancy test will be positive during the missed period or 14-15 days after implantation (which may already be a few days before the missed period).

Other potential cellular sources of hormone synthesis may include: hyperglycosylated hCG produced by cytotrophoblast cells, a free beta subunit formed by several primary non-trophoblastic malignant neoplasms, and pituitary hCG produced by gonadotrope of the anterior pituitary. Therefore, the definition of different types of hCG has a different meaning.

The functions of hCG that is synthesized by the trophoblast are very wide. It provides the promotion of luteal progesterone production in a woman’s body, which supports pregnancy. HCG provides angiogenesis (vascular formation) of the uterus vascular network. It provides differentiation of cytotrophoblasts, immune suppression and blocking phagocytosis of invading trophoblast cells. HCG affects the growth of the uterus in accordance with the growth of the fetus, as well as the promotion of growth and differentiation of the fetal organs. The growth and development of the umbilical cord also provides hCG. The hCG receptors in the adult cerebral hippocampus, hypothalamus and brainstem can cause nausea and vomiting during pregnancy. The hormone has many other roles, including stimulating fetal steroidogenesis, and high levels have been teratogenic in the gonads of the fetus.

HCG is a marker that has the potential to predict the likely outcome of pregnancy from the moment of conception and is more informative than other means.

Pregnancy monitoring. To a lesser extent, levels of hCG were examined to assess the potential for the duration of pregnancy. HCG levels are also being investigated along with other biochemical and physical markers for the use of prediction of a genetic abnormality during pregnancy.

That is why it plays a decisive role in a woman’s body, not only during pregnancy, but also before pregnancy.

Indications for the procedure HCG during early pregnancy

The indications for testing for hCG are limited to three main reasons. The first and main reason is the detection of a normal pregnancy. Pregnancy testing is performed during amenorrhea examination, to confirm the clinical signs and symptoms of pregnancy and for early detection of implantation. Although a qualitative assessment of hCG is usually sufficient, a quantitative measurement has been proposed as a valuable means of estimating the early gestational age when the logarithm of hCG is compiled according to the gestational age.

Secondly, it has been shown that hCG has value in detecting and subsequent observation of a potentially abnormal pregnancy. Patients with an ectopic pregnancy, threatened or incomplete abortion, usually have low concentrations of hCG in the blood for the gestational period. These features are useful in evaluating a patient with abnormal uterine bleeding or abdominal pain, when a qualitative measurement of hCG revealed the presence of trophoblast tissue. Quantitative analysis of hCG in combination with ultrasound scanning is recognized as valuable additions to the assessment of the clinical features of the course of pregnancy.

Indications for measuring hCG are also monitoring of tumor activity, in particular, gestational trophoblastic disease (choriocarcinoma). These tumors secrete large amounts of hormone, which allows the use of hCG tumors to monitor the progress of the disease.

[1], [2], [3]

Preparation

Preparation for the analysis of the determination of hCG depends on the method and conditions of this analysis. If a woman has the goal to determine qualitatively the presence of hCG in the urine at home, then a certain preparation is not required. The analysis is carried out in the morning on an empty stomach when the maximum amount of hCG in the urine is expected during pregnancy.

If it is necessary to control or determine the hCG in the blood, then there are some conditions. The analysis is also carried out on an empty stomach. Blood is taken from a vein, so the day before it is important to stick to a healthy diet with the exception of fatty foods and harmful substances.

Technique HCG during early pregnancy

The technique for determining hCG depends on the method used. Immunological methods today have many advantages. Quantitative assays are widely used to measure serum hCG and are usually based on ELISA or IRMA methods. The main thing you need to know about the technique of conducting - is that a woman takes blood from a vein, and then with the blood they analyze on special installations and determine the level of hCG.

The apparatus for analysis may have different modifications.

What hCG during pregnancy in the early stages? As already mentioned, the rate of hCG in pregnancy in the early stages of 25 to 5000 mIU / ml. In the first 2–4 weeks after fertilization, hCG usually doubles every 48–72 hours. An increase of 35% within 48 hours in early pregnancy is considered normal. If its level is 1200 mIU / ml, hCG usually doubles every 48-72 hours. The maximum level is usually reached on the 10th or 11th week. After 10 weeks or so, hCG usually decreases.

Normal performance

The level of hCG in the urine rises at least 6 days after the estimated day of conception. Levels of hCG grow rapidly in the earliest days of pregnancy and can be detected very early. The moment when hCG can be detected for the first time depends on the method used to evaluate the concept and the sensitivity of the hCG analysis. Several studies have shown that hCG is detected in the mother in the urine on day 6 or more after the estimated day of conception. Plasma hCG can be detected on day 8 after conception. However, these analyzes rely on extremely sensitive measurements made under precise conditions.

Since hCG is produced by trophoblast cells, it should not be determined if there is no pregnancy. Therefore, HCG rate in non-pregnant women is a negative test or its numerical value from 0 to 5 units. If a non-pregnant woman has an increase in hCG, then you need to look for the cause.

Technically, hCG tests are designed to qualitatively detect or measure hormone in urine or blood, and there are other reasons besides pregnancy that can cause hCG. Here are some of these reasons.

1. Biochemical pregnancy. Biochemical pregnancy occurs when a woman is pregnant, but has a spontaneous loss of the fetus, before she even learned that she is pregnant. If hCG testing occurs before all hCG has been metabolized from the body, then hCG can be detected by laboratory test. This situation is not as unusual as one might think for two reasons. First, hCG tests are often performed in medical institutions to identify a pregnant patient in order to avoid any medical interventions that are potentially harmful to the fetus. Secondly, hCG tests can detect very low hormone concentrations. The high frequency of testing combined with the analytical sensitivity of the tests means that biochemical pregnancies are easily detected.
2. HCG pituitary gland. Although the placenta usually produces hCG during pregnancy, this function can also be performed by the pituitary gland. The pituitary gland is a small structure in the brain that secretes many different hormones that function to regulate many endocrine organ systems. Interestingly, the three hormones, usually produced by the pituitary gland (thyroid-stimulating hormone, follicle-stimulating hormone and luteinizing hormone), are structurally similar to hCG. Pituitary hCG is more commonly found in women over 55 years old, but can be found in women under the age of 41 years. Non-pregnant women with pituitary hCG usually have low concentrations of hCG present in the blood and urine. It is important to note that the concentrations of hCG produced by the pituitary gland do not show the rapid increase that is observed during pregnancy.
3. Cancer cells sometimes produce hCG. Although many types of cancer have been shown to have a hormone, it is most commonly associated with gestational trophoblastic diseases and some types of testicular germ cell tumors.
4. Interfering antibodies. Some women have antibodies in the blood that can affect hCG tests and cause a positive or elevated result in the absence of hCG. This problem can only be subjected to blood-borne hCG testing, since the molecules of the interfering antibody are usually not present in the urine. This can be a serious problem because some women mistakenly diagnosed cancer because of a false-positive hCG test result and underwent unnecessary treatments. During the past few years, manufacturers of hCG tests have worked to minimize the potential for interference from these antibodies, but do nothing to completely eliminate the problem.

Thus, just because the result of the HCG test is interpreted as positive does not automatically mean that the woman is pregnant. There are very good reasons for detecting hCG in the absence of pregnancy. However, when the result of the hCG test does not match the clinical picture, the question of the reliability of the values obtained must still be asked in the laboratory.

In 85% of cases of normal pregnancy, the level of hCG doubles every 48 to 72 hours. As you get farther during your pregnancy and your hCG level gets higher, the time you need to double can increase to about 96 hours. The level will reach its peak in the first 8-11 weeks of pregnancy, and then decrease for the remainder of the pregnancy.

Care should be taken when creating too many hCG numbers. Normal pregnancy can have low levels of hCG and lead to a perfectly healthy baby. The results of ultrasound after 5-6 weeks of pregnancy are much more accurate than the use of hCG numbers.

HCG is measured in milli-international units per milliliter (mIU / ml). There is a wide range of normal levels and values of hCG, and the values are different in serum or urine. Urine hCG levels are usually lower than serum hCG levels. Blood testing for hCG is much more sensitive than urine HPT. This means that a blood test can detect pregnancy a few days earlier than a urine test, 2-3 days after implantation or 8-9 days after fertilization.

A hCG level of less than 5 mIU / ml is considered negative for pregnancy, and anything above 25 mIU / ml is considered positive for pregnancy.

A hCG level between 6 and 24 mIU / ml is considered a gray area, and you will probably need to be re-tested to see if the levels are rising to confirm pregnancy.

Urine tests qualitatively evaluate hCG, which means that the results are either "positive" or "negative." During the first missed period (14+ days after ovulation), more than 95% of hCG is usually positive.

Blood hCG levels are not very useful for checking the viability of pregnancy if the hCG level is above 6000 or after 6-7 weeks of gestation. Instead, in order to better check the health of the pregnancy, a sonogram must be performed to confirm the presence of a fetal heartbeat. As soon as fetal heartbeat appears, it is not recommended to check the viability of pregnancy with hCG levels.

Levels of hCG are also higher in women carrying the female fetus, compared with women carrying the male fetus, so it is possible that the pregnancy test will be positive later in women carrying the male fetus.

There are two common types of hCG tests. The qualitative hCG test simply looks to see if there is hCG in the blood. A quantitative hCG (or beta hCG) test measures the amount of hCG actually present in the blood.

HCG during pregnancy by day has differences that must be considered when interpreting the data. But one level of hCG cannot be assessed in the context of the course of pregnancy and the health of this pregnancy, it is necessary to evaluate the data of hCG together with clinical changes.

HCG for weeks depends on gestational age:

• 3 weeks: 5 - 50 mIU / ml
• 4 weeks: 5 - 426 mIU / ml
• 5 weeks: 18 - 7 340 ml / ml
• 6 weeks: 1080 - 56 500 mIU / ml
• 7-8 weeks: 7, 650 - 229 000 mIU / ml
• 9-12 weeks: 25 700 - 288 000 mIU / ml
• 13 - 16 weeks: 13 300 - 254 000 mIU / ml
• Week 17 - 24: 4060 - 165 400 mIU / ml
• 25 - 40 weeks: 3,640 - 117,000 mIU / ml

1. Non-pregnant women: 0 - 5 mIU / ml
2. Postmenopausal women: 0 - 8 mIU / ml

These numbers are only a guideline - the level of hCG of each woman can grow in different ways. This is not necessarily the level that matters, but rather the level change.

[4], [5]

Raising and lowering of values

There is a wide range of normal hCG values and the values are different in serum or urine. There is no single normal human chorionic level of gonadotropin, which always indicates a healthy pregnancy. Therefore, elevated hCG during pregnancy in the early stages has a rather broad concept. Determining what constitutes a “high” level of hCG may be difficult, since the normal range of levels of hCG in early pregnancy is wide, and the levels of hCG can rise and fall at different rates. Depending on how far you are in your pregnancy, there are general guidelines that doctors use. Usually an increase in hCG levels will usually be a level that rises by more than 60% within 48 hours.

High levels of hCG may indicate several different things, most of which are not so important. This may mean that the calculation of your pregnancy date is incorrect and that you are further than previously thought. It can also mean that you have more than one child, like twins. If you take fertility drugs, your levels of hCG also increase.

The level of hCG with twins is higher than with single-parent pregnancy, since two trophoblasts work and synthesize more hormones. However, it is impossible to diagnose a double pregnancy only from hCG. There is not enough scientific evidence that with twins there is always a faster than usual increase in hCG. Normal hCG values can vary up to 20 times during normal pregnancy. Variations in increasing hCG are not necessarily a sign that pregnancy is abnormal or that there are two or more fetuses.

Lowering hCG during pregnancy in the early stages is more informative than raising it. The estimated childbirth date is calculated based on your last menstrual period. If you have a history of irregular periods or you are not sure about your last menstrual period before pregnancy, it may be more difficult to tell how far you are in your gestational age. If your pregnancy is very early or after 12 weeks of gestation, hCG levels may be low. Ultrasonic and repeated levels of hCG may be required to correlate levels of hCG and gestational age.

Miscarriage - a spontaneous loss of pregnancy to 20 weeks of pregnancy. Miscarriage can lead to lower levels of hCG. Pregnancy that does not develop the placenta cannot produce higher levels of hCG. In such cases, the levels of hCG may be normal initially, and then decrease in case of miscarriage.

A precipitated egg occurs when the egg is fertilized and attaches to the wall of the uterus, but does not develop. Cells develop a gestational sac and can release the hormone hCG, although the fertilized egg does not develop further. Such a frozen pregnancy can eventually cause a decrease in hCG, because only the first time it grows, and then the level decreases, since there is no development of the fetus.

An ectopic pregnancy occurs when a fertilized egg is deposited inside the fallopian tube, a tube that carries an egg from the ovary to the uterus or outside the uterus. An ectopic pregnancy is a life-threatening condition, as it can rupture the fallopian tube and cause bleeding. Levels of hCG can help differentiate a normal pregnancy from an ectopic pregnancy, since the level of hCG in an ectopic pregnancy will be lower than expected for gestational age.

In early pregnancy there are two hormones that, as a rule, increase in the body after implantation - progesterone and human chorionic gonadotropin. Both hormone levels tend to increase in women with viable pregnancies, but in women with an expected miscarriage. And in the past few decades, it has become generally accepted that doctors prescribe progesterone supplements to women with recurrent miscarriages, and the idea is that underproduction of progesterone may be the cause of miscarriage.

However, progesterone is a subject of debate among doctors, as many believe that low progesterone is a sign of a failed pregnancy, not a factor contributing to a failed pregnancy, and progesterone supplements have not yet been proven for women at risk of miscarriage.

Much less attention is paid to the idea of supplementing another pregnancy hormone - hCG - to prevent miscarriages, although hCG is a hormone measured in home pregnancy tests and sequential blood tests used by doctors to assess the viability of early pregnancy.

Injections of hCG during pregnancy in early pregnancy can be helpful in preventing miscarriages, since it is known that endogenous hCG plays an important role in establishing pregnancy. Hormonal hCG plays a key role in helping to establish a pregnancy, and it is theoretically possible that reducing hCG production may play a causal role in miscarriages. In most cases, these injections may be required during the first trimester of pregnancy, and sometimes in the second trimester. As the embryo grows, the amount of hCG secreted increases significantly. In other words, an adequate supply of it is necessary for normal development during pregnancy.

Existing studies have shown that treatment can benefit women with infrequent and irregular periods (oligomenorrhea). But, unfortunately, this does not mean that you should go to your doctor and ask for an early hCG injection at the next pregnancy, even if you have oligomenorrhea. Too little is known about whether this treatment works. Assuming that it even works, more research is needed before treatment can be widely used.

If you take an hCG injection during ovulation, this may increase your chances of multiple pregnancies.

Injections of hCG can cause certain side effects. To begin with, since hCG is a pregnancy hormone, it can cause and aggravate some of the common symptoms associated with pregnancy, such as nausea, breast tenderness. Some other mild side effects associated with hCG injections include water retention, headache, irritability, fatigue, abdominal discomfort, and soreness at the injection site. Women who take injections of hCG during pregnancy are also at risk of developing ovarian hyperstimulation syndrome. This is a health condition that can be life-threatening. This can cause severe abdominal and pelvic pain, shortness of breath, nausea, vomiting, diarrhea, rare urination and even edema of the limbs.

In fact, the risks associated with taking pictures of hCG during pregnancy far outweigh the benefits that it offers to the mother and baby. Therefore, it is important that you take it after consulting only with a gynecologist.

HCG during early pregnancy may be the first sign that confirms that you are really pregnant. Further monitoring of this indicator can tell you about the state of your pregnancy, but only when assessing the clinical data of the course of pregnancy.

[6], [7], [8], [9], [10]