Women seeking to become pregnant know well what is chorionic gonadotropin (HCG or hCG). This hormone begins to be produced immediately after successful conception. The growth of hCG in the days after implantation allows you to track the course of pregnancy.
Chorionic Gonadotropin
The hormone is produced by the tissues of embryological structures. Its level becomes noticeable about a week after fertilization of the egg. It is then that you can establish the beginning of pregnancy by special pharmacy tests, the principle of action of which is based on determining the presence of the hCG beta subunit in urine. However, to confirm the physiological process, a quantitative determination of the hormone in the blood will be required, since this analysis is more accurate.
HCG refers to a subclass of tropic hormones of the anterior pituitary and placenta, along with similar substances it regulates the human sex glands. Its chemical structure is formed by 237 amino acids, which determines its molecular weight of 36.7 kilodaltons.
Chorionic gonadotropin is a two-component protein, the peptide part of which is covalently linked to a hetero-oligosaccharide. The same class includes luteinizing hormone (LH) and follitropin (FSH), but although their alpha subunit is homologous to hCG, the beta subunit contains a different amino acid sequence.
The growth of hCG in the days after implantation obeys a certain regularity: up to 7-11 weeks of pregnancy, its level increases several thousand times compared to the initial one, and after reaching a maximum it gradually decreases. However, a drop in concentration or growth retardation that occurs long before 7 weeks is an alarming signal, as it may indicate an ectopic pregnancy or miscarriage. Therefore, it is important to know exactly the norms of HCG readings.
Biological properties
HCG binds to gonadotropin receptors and has both luteinizing and follicle-stimulating activity. Moreover, the first type of activity is strongly expressed and surpasses even luteinizing hormone.
One of the main signs of pregnancy - cessation of menstruation - is due to an increase in hCG in the days after implantation. Without this hormone, the corpus luteum of the ovary exists only about two weeks after the menstrual cycle, after which it dissolves. However, chorionic gonadotropin does not allow him to do this, and the temporary gland continues to be functionally active for 10-12 weeks. During this time, it produces estrogen and progesterone instead of the placenta. Moreover, the last sex hormone is produced in very large quantities, impossible in the absence of pregnancy.
In addition to estrogens and progesterone, the body of a pregnant woman produces weak androgens. They relate to male sex hormones. By themselves, they cause relaxation of the muscles of the uterus, but too high a concentration of these substances threatens to halt the growth of the size of the uterus. This leads to the fact that the fetus becomes crowded in it, which threatens to miscarry.
Another property of hCG is adrenocorticotropic. This means that the hormone increases steroidogenesis in the adrenal cortex, which contributes to their functional hyperplasia. As a result of increased secretion of glucocorticosteroids by the glands, the pregnant body adapts to stress, and physiological immunosuppression is provided. The latter is necessary so that the uterus does not tear off the organism that is half alien to it.
How the hCG level changes in the days after implantation also affects the placenta. With normal indicators, it develops correctly and has good functional activity. Her trophy is improving, and the number of chorionic villi is increasing.
Exogenous administration
HCG can enter the body from the outside. In this case, in the middle of the cycle, women increase the production of female sex hormones by the ovaries, and ovulation is also stimulated. After this, the bursting follicle undergoes luteinization, and the function of the corpus luteum continues to be carried out.
If an hCG is administered exogenously to a man, spermatogenesis and the production of sex hormones will be stimulated in his body.
HCG growth chart days after implantation
The indicators of the level of chorionic gonadotropin, depending on the gestational age, are not strict and can vary. But in general, they should have approximately the form that is indicated in the hCG table by day:
After IVF, the indicators vary over a wider range, and their maximum is higher than with conventional fertilization. This can be seen in the following table:
The specific indicator will depend on the individual state of the body, as well as on the equipment of the laboratory in which the analysis was carried out.
Sometimes pregnancy occurs without a detectable increase in hormone levels. This is possible too early and when the fertilized egg is attached outside the uterine cavity.
Features of in vitro fertilization
If for some reason people cannot become parents naturally, fertilization is possible through medical intervention. For this, a complex multi-stage procedure is carried out called in vitro fertilization or IVF for short. It involves the fertilization of an egg in a laboratory environment and the transfer of an embryo into the uterus. At the same time, when the implantation of the embryo after IVF occurs, it may slightly differ from the timing of the natural conception.
So, normally an egg is attached to the uterine cavity after 7-10 days from conception. The process lasts about 40 hours. Very rarely, but sometimes there are still cases when the implantation is carried out after 6 days, then implantation is characterized as early. Such a shift in terms is not favorable due to insufficient preparation of the internal mucous membrane of the uterus - the endometrium. The hCG growth rate after implantation does not change.
After IVF, the process is usually delayed on the contrary. The introduction takes place after 10 days and in itself takes about 72 hours. Due to the late implantation of the embryo during IVF, hCG does not grow immediately. It is not necessary to worry because of this, since for fertilization in artificial conditions this is quite natural.
However, future parents are usually very worried about whether the implementation has passed, and look for signs that everything is safe. Subjectively, the following symptoms may indicate this:
- scanty beige or pink discharge, which appears when the endometrium rich in blood vessels is damaged by an embryo;
- pain in the lower abdomen, similar to those that occur when menstruation approaches;
- nausea and metallic taste in the mouth;
- temperature increase to 37.2 degrees;
- weakness or dizziness.
However, these symptoms cannot be considered as confirmation of pregnancy, as they may indicate any other changes in the body. A more reliable sign is an increase in basal temperature, however, the final diagnosis of successful fertilization is carried out according to the results of an ultrasound examination carried out on the fifth day after embryo replanting and repeated 10 days later.
Another reliable criterion is the level of chorionic gonadotropin. For those who want to know how fast changes are occurring in the pregnant woman’s body, there is a table of hCG growth rates daily after IVF.
Sometimes a gynecologist uses such a concept as the day after ovulation, or, in short, DPO. The growth of hCG by days of DPO is absolutely similar to the above table of norms after IVF.
Deviations from the norm
If the level of the hormone is very different in one direction or another from the indicators shown in the hCG table for days with IVF or conventional fertilization, additional examinations are urgently needed. Too low a concentration of chorionic gonadotropin may indicate the following disorders:
- ectopic or non-developing pregnancy;
- delay in the development of the unborn child;
- placental insufficiency;
- perenashivanie fetus.
Of great importance is how low the level of hCG is, and how long a woman is currently at. For example, if it is no more than half of normal values, a pregnant woman may experience spontaneous abortion. And if the decrease occurred for a period longer than 3 months, fetal death is possible.
Increased chorionic gonadotropin may also indicate any abnormalities, for example:
- diabetes in the mother;
- preeclampsia, that is, a complicated pregnancy, accompanied by edema, increased pressure, loss of protein, seizures;
- chromosomal abnormalities of the fetus.
In the latter case, a prenatal definition of Down syndrome in the unborn child is necessary. It is diagnosed with a decreased level of pregnancy-associated A-plasma protein.
In addition, hCG may be elevated when the mother takes synthetic progestogens. However, a high level of chorionic gonadotropin is not always a bad sign. It can also indicate a multiple pregnancy (it rises as many times as the fetus develops in the uterus) or an incorrect setting of the term.
HCG Tracking
The growth of hCG in the days after implantation is monitored by a blood test. In order for the result to be true, you need to prepare for the study: do not eat food 8 hours before blood sampling, avoid drinking alcohol and smoking, try to avoid stressful situations and overstrain. You need to come to the analysis in the morning.
Blood will be drawn from the peripheral vein. Since plasma is needed for the study, the selected material is centrifuged and the blood cells separate. Direct determination of the level of hCG is carried out using additional reagents.
Recommendations for pregnant women
The growth of hCG occurs correctly if intrauterine development occurs normally. For this, the expectant mother needs to follow some simple recommendations. First of all, they relate to bad habits.
Smoking is unacceptable, especially in the early stages, and it must be abandoned before planning a pregnancy, or at least immediately after it became known. It will be necessary to give up smoking completely, a gradual decrease in the number of cigarettes smoked per day is inefficient and harms the baby.
Even someone else's cigarette smoke can have a negative effect, so smoking areas should be avoided. The same goes for alcohol.
The prohibition on a fairly large list of drugs can cause difficulties. Due to the fact that the body experiences some stress during pregnancy, a slight malfunction occurs in the immune system, and a woman can easily get sick. However, many medications are prohibited during pregnancy, especially antibiotics. Without consultation with a gynecologist, no funds can be taken.
During pregnancy, you can not take an x-ray, because its rays destroy the fetal tissue and can cause abnormalities in the development of an already born child. You should also refrain from lifting weights. Usually everyone knows this, but many neglect this, and a frivolous attitude to this aspect threatens to increase the tone of the uterus or even detachment of the placenta.
Vapors of household chemicals can negatively affect the fetus, so it is better not to use aggressive substances such as "Schumanita". The same applies to strongly smelling varnishes, paints, adhesives, insecticides.
During the gestation period, animals, including their own pets, can be a danger. They can initiate toxoplasmosis, and in order not to get infected, you will have to wash your hands thoroughly after each contact with them.
The common misconception that the expectant mother needs much more is fundamentally wrong. You need to rethink your diet in terms of quality, not quantity. This means that junk foods should be replaced with vegetables, fruits, whole grains and high protein foods.
Take the recommendations very seriously so that the main systems and organs of the baby are healthy.
What else can hCG indicate?
Sometimes hCG growth and implantation are not related. This hormone is determined in the blood of non-pregnant women and even men. Unfortunately, chorionic gonadotropin is secreted not only by the placenta of the fetus, but also by some malignant tumors. This process is called ectopic production. In this regard, with an hCG index of more than 5 milliunits per ml of blood, the following serious diseases can be diagnosed:
- testicular tumors in men or uterus in non-pregnant women;
- neoplasms in the gastrointestinal tract, lungs or kidneys;
- the formation of a conception product without the normal development of the embryo, accompanied by the proliferation of villi in the form of liquid bubbles;
- chorionic carcioma.
To determine exactly what is happening in the body, you need to conduct additional examinations. The prognosis for elevated hCG is not always alarming, because sometimes it turns out to be an analysis error or it is caused by taking any medications in front of him, primarily hormonal ones. In women, increased hCG without pregnancy may be the result of a recent abortion, after which not all hormones have returned to normal. In any case, the study is better to repeat, for which you may have to go to another clinic.
Conclusion
Of course, it is best when the growth of hCG is due to positive reasons - a planned pregnancy. To ensure its increase within the norms will help a woman's careful attitude to her well-being and health and following all the doctor's recommendations.
The specialist will tell you how often to donate blood to hormones, and independently decipher the results. Roughly knowing what the growth should be, according to the tables, a woman can be calmer for her baby. However, it must be remembered that the result is influenced by many factors, for example, with late implantation of the embryo, hCG may begin to grow a little later than usual, so you should not worry about small deviations if the doctor claims that everything is in order.