If a newborn karapuzik fusses for two hours in a row, or if a three-year-old mischievous man is already kidding, Mom or Dad jokingly declares to each other: "These are all your family genes!" Indeed, genes decide if not all, then much. Thus, both the color of the hair, and the cut of the eyes, and the constitution of the body, and even some character traits, a little man, willingly or unwittingly, inherits. To influence this, fortunately or unfortunately, a person can not yet (cloning people and interfering in "God's craft" at the stage of the birth of a new life are prohibited by law). However, there are cases when without the help of geneticists the appearance of a healthy child is put under the big question ... So, to visit "the rulers of genes", mom and dad have seven reasons ...
1. Preparing for pregnancy
Now many young couples, still only submitting an application to the registry office, are planning a time for the appearance in their family of a small fruit of love. Although when this time comes, the future mom and dad are more concerned that their baby by the sign of the Zodiac must necessarily be Capricorn (Lion, Aquarius ...) and a representative of the desired - strong or beautiful - sex. About, to hand over the analysis of a blood or to consult with the geneticist, speech, as a rule, does not go. Or it goes, if there has already been trouble with conceiving or bearing pregnancy. Why is the office of a geneticist physician bypassed? Scary? Willingly believe. However, in reality, there is nothing intimidating in the medical genetic counseling, but among you, among the abundance of idle "horror stories" about pregnancy, there will be no cause for special excitement.
The geneticist will make a pedigree, determine if your family is at risk for hereditary diseases, and recommend that you carry out the studies necessary to prevent a possible genetic pathology in a future baby. It happens that even a parent who is safe from the point of view of heredity can experience a "malfunction," and a baby whose health, it would seem, does not threaten anything, under the influence of a number of external factors, risks appearing with an inborn violation. Therefore, the geneticist's task is not only to ask parents about hereditary ailments, but also to find out whether there are any harmful effects in the life of potential moms and dads that could affect the health of their unborn child (for example, radioactive exposure, work with chemical reagents and so on), and to determine the probability of the birth of a baby with one or another disease. Unfortunately, healthy parents who are planning a child are still very rarely addressed to geneticists, and, in fact, according to medstatistiki, even in a perfectly healthy couple, the risk of having a baby with a chromosomal breakage is 5-10%. If the family does not fall into this number, it seems quite small. And if it hits? ..
2. It is impossible to conceive a child or to endure pregnancy (spontaneous miscarriages)
Sometimes the genetics office for such families is the last instance. They turn to him, having already got into a practically hopeless situation. Stereotypes are strong, and if a woman has no children for a long time or there are regular miscarriages, relatives blame it on the woman ... The worst thing is when a woman herself begins to believe that she "is not capable of having a healthy child" and deprives herself of the hope of becoming mother. Often, the whole problem is that the genetic imbalance in the embryo (the gomet formed by the fusion of the mother and father's sex cells) leads to the fading and rejection of the fetal egg at extremely early development times (during the first days or hours after conception). And this may not even be accompanied by a delay in the monthly and there may not be any signs of pregnancy. Sometimes couples can undergo years of examination and treat infertility or miscarriage of pregnancy, without thinking that the main reason for all the failures are precisely genetic factors. A routine consultation at a medical genetic center and carrying out genetic tests during pregnancy will clarify the most vague situation and help settle conflicts. For this purpose, prospective parents are usually offered the same blood test for determining the karyo type. And the study of chromosome recruitment is a mutual affair, because the baby gets half of the chromosomes from his mother, and the second - from the pope.
3. The age of the future mother - for 35, and the popes - for 50
It should be noted that although the reproductive age of modern women has increased to 40 years, and the prickly phrase "old primitive" for mothers older than 25 has practically left the lexicon of even doctors with an enviable experience, the course of time is inexorable - the female eggs grow old. After all, they are older than the woman's body by ... 4.5 months and in this "composition" live and mature in her body during the entire childbearing age. Spermatozoa are refreshed every 72-80 days. So, it happens that an aging egg due to its own age does not always cope with the "responsibilities" for the highest category - the risk of mutations increases with age. Genetics operate with rigid statistics: for 900 genera of 25-year-old women there is one child with a down syndrome, already at 35-year-old the risk of having a baby with such a pathology, unfortunately, increases three-fold ... But the giving birth at age 45 and older is especially scrupulous, because the chromosome breakage occupies every 24th newborn. These facts do not at all taboo on the desire and ability of the mother, who is over 40, to become pregnant and have a baby. Just to avoid a bitter mistake, it is worthwhile to visit genetics on time and adhere to its recommendations.
4. Features of the course of pregnancy
Pregnancy has already declared itself by two strokes on the test. Mom accepts congratulations from relatives and friends, starts to monitor her diet (she changes the breakfast consisting of coffee and a piece of chocolate, yoghurt and gruel from unpolished rice), subscribes to a magazine for parents and "prescribes" in a women's consultation. When the future mother is registered (and with this it is worth hurrying to the 8-10th week of pregnancy), the obstetrician-gynecologist will necessarily ask her about the illnesses, previous pregnancies, about the current pregnancy. In a word, the following reasons can guide the decision of a gynecologist to forward a future mother to genetic tests:
♦ hereditary disease in one of the parents of the future baby;
♦ birth of a previous child with developmental or chromosomal pathology;
♦ The age of the future mother is over 35;
♦ impact on teratogens of mother and baby: if a woman before 12 weeks of pregnancy took strong drugs or even dietary supplements, or alcohol. Regarding the last factor, it is worthwhile to be vigilant, especially if there is a suggestion that an unplanned conception occurred just after the party, where the future mom or dad were under the driver.
5. Results of ultrasound examination
The first examination is better to pass earlier than is required by the generally accepted ultrasound calendar, in the first 4-5 weeks. At this stage, the doctor can make sure that the fetal egg is located, as expected, in the uterine cavity, or has an unwanted "dislocation" (there is a risk of an ectopic pregnancy).
The second ultrasound should be done no later than 11-14 weeks, when the doctor can and must perform the most accurate diagnosis of certain malformations and identify changes signaling a possible chromosomal pathology - and then the woman is sent to the genetics. The specialist will most likely prescribe a more thorough examination using a method that allows you to get cells from the placenta and accurately determine the chromosome set of the baby during pregnancy (chorionic biopsy, amniocentesis). The third (second planned) ultrasound is best done at week 20-22. This period makes it possible to determine deviations in the development of the face of the baby, limbs, and also to identify possible deviations in the development of the internal organs of the fetus. The most important thing at this stage is not even the diagnosis itself, but the opportunity to treat the baby in the womb or to prepare for the special course of this baby's birth, in advance to determine the optimal tactics of the subsequent treatment until the child's complete recovery.
6. Analysis of biochemical tests
If we ask the ordinary future mothers what they would like to erase from their pregnancies, probably all 100% would answer: "Infinite analyzes." But this, albeit not the most pleasant, term of the "interesting situation" can not be abolished, because sometimes it is the usual blood test that reveals the alarming factors. The indicators of possible malfunctions are components of plasma protein, alpha-fetoprotein and chorionic gonadotropin - special proteins that are produced by embryonic tissues. When the concentration of these proteins in the blood of a future mother changes, it is possible to suspect possible violations in the development of the fetus. The study of such markers is carried out on certain dates:
♦ level of plasma protein and chorionic gonadotropin - at 10-13 weeks of gestation;
♦ Chorionic gonadotropin and alfa-fetoprotein - at 16-20 weeks. The results of the blood tests that Mom gives in the women's consultation lab, get to a gynecologist, who has a woman during the entire pregnancy. If there is cause for concern and additional examination, the attending physician at the next reception or by phone informs Mom about the need to visit the genetics and pass the genetic tests.
7. Acute conditions in prenatal infections
Oh, these infections ... But they, insidious, sometimes do not bypass the future mother, but, on the contrary, "cling" to her body or, being so far in the concealed state, begin to progress. The reason for this - and somewhat weakened by pregnancy immunity, and untreated foci of infection, and just a seasonal infection, from which no one is immune.
Some viral infections (herpes, rubella, cytomegalovirus, toxoplasmosis) during pregnancy can cause impaired development of the fetus (which is why such infections are often called intrauterine). It is advisable to conduct a screening test for virus detection prior to conception or during the first weeks of the period, when it is still possible to prevent their influence on the baby. If the consequences occur in the second or third trimester - all can end sadly.
Why do chromosomal abnormalities occur?
Genetics knows the answer to this question. The fact is that a suitable society for a chromosome is a pair. Ideally, after the merger of my mother's and father's sex cells, the process of further division into cells with the same set of chromosome "pairs" is going on-23 mothers and 23 daddies. But it happens that a third chromosome adjoins the pair for "own reasons" - and such a trio (scientifically, trisomy) is the culprit of congenital malformations. In any case, modern medicine has the ability to identify these defects in advance. And it helps in this passage of genetic tests during pregnancy. So do not be afraid of this method of diagnosis - and be healthy!