Pregnancy
Beginning
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Screening studies: invasive and not invasive
The screening studies are those who allow the precocious detection of illnesses or malformations in the baby. The studies I predepart from screening they have ethical complications when it has not to do with the maternal health and there are simply a product of the curiosity of the parents. Although for the anxiety that generates the information about they, every day more doctors indicate these studies, which in general are expensive. In contrast to the studies of screening neonatales, which can only be done when the child was already born (for example fenilcetonuria, hepatitis or the screening of the congenital hipotiroidismo) in that an important justification exists, since the treatment the more precocious, most successful in these cases. On the other hand, in the studies of screening prechildbearing there is not greatly for doing and scarcely it is possible to gloat in spite of finding out about something earlier for the technological advantage.
It is necessary to remember that the studies of screening, like his name it are indicated by it (in English screening it is "pantallazo"), they have an epidemiologic utility, that is to say, that overcomes the individual case. In any case, there talks each other of an intimate conviction of the couple gestante the decision to realize these studies. The screening is indicated in general when there are already precedents in the family of genetic problems. Here we will see the most common types of screening in the prechildbearing. We will begin for the not invasive ones.
Triple screening:
This is a study that measures three substances earlier mentioned, simultaneously:
- Alfafetoproteína
- Free Estriol
- Human Gonadotrofina coriónica
It is realized about semana16 of pregnancy. It is done by means of a blood extraction of the mom gestante. Or that is not an invasive method. It does not give an exact result, only it indicates if there is an increase in the alterations risk in the fetus, so much chromosomal; as of forked thorn; alterations in the head; or if it is a multiple pregnancy; or risk of high arterial tension in the mom; congenital arterial or cardiac malformations; etc.
The result that throws this study, can give the rule to the medical dealer to decide if it is necessary to keep on investigating with some another study, like for example an amniocentesis.
Biopsy coriónica:
This study has a diagnostic accuracy of 99,99 %. (Seldom there is 100 % in the medicine, they say...)
It is realized under control ecográfico as he guides, obtaining a small sample of the afterbirth that, after being processed, any chromosomal anomaly of the baby will be able to be diagnosed, and his sex. It is realized between the weeks 11-14 of the absence of menstruation. His result stays on approximately 5 days.
This study has 2 advantages:
- That can be realized by a little pregnancy time,
- That his result is very rapid and exact.
Analysis of Alfafeto protein or AFP in blood during the pregnancy:
The alfafetoproteína, is a protein that forms in the liver of the fetus. This protein measures itself (by means of a blood test) to confirm or to discard anomalidades in the baby. It is realized between the week 15-20 of the pregnancy. The result stays on 72 hours. If the above mentioned study should reflect an increase of the Alfafetoproteína, it might be indicating the possibility of:
Syndrome of Turner: Genetic syndrome, which does that the women do not develop sexually, and remain low, sometimes late mentally, and they have only one chromosome x.
Multiple pregnancy: More than one fetus.
Atresia duodenal: It is the absence of opening of the first part of the small intestine.
Onfalocele: It is the exit of the intestines for the orifice of the bellybutton, a development of the wall of the abdomen.
Anencefalia: It is the absence of closing of the pipe at level rostral, it generates an absence of cerebral, incompatible development with the life.
Forked thorn: Lacking in the closing in the caudal pipe, which is compatible with the life. It is possible to operate if it generates inconveniences.
Tetralogía of Fallot: Congenital cardiac and arterial malformation, which gives heart failure, can occur.
If in the blood test, the Alfafetoproteína should give under the normal values, this might be indicating the possibility of: Loss of the pregnancy, or enclosed being a predictor of the Syndrome of Down
NT Bonus 11-14:
It consists of a study ecográfico specializing and a blood test. It is the method of calculation of very effective risk. It detects up to 85 % of the cases of pregnancies with some chromosomal anomaly of the most frequent. 14 is realized between the weeks 11. And his result is late 48 hours. The advantages of this study are:
1 - The rapidity of his result
2 - That can be realized by a little pregnancy time
3 - That is not an invasive study, therefore it is not risky for the baby.
Invasive studies: the amniocentesis
This study consists of doing a puncture in the abdomen of the mom, to extract a sample of amniotic liquid. This study allows to detect chromosomal anomalies or simple genetic disorders.
Also it allows to diagnose uterine infections; and it helps to determine the gravity of a fetal anemia; and to determine if a blood transfusion is necessary. It is possible to realize in the week 18 of the pregnancy. There are usually indicated moms of more than 35 years, or with precedents of chromosomal illnesses. This study has some disadvantages:
- It is an invasive study, as what it has a percentage of risk. (Abortion or infection)
- His result is late very much, between 2 to 3 weeks. For which, it produces many anxiety.
Although it is not painful, yes it is annoying and it impresses a little. Also after the test, there can be small losses of blood.
- And he needs 24 hours of rest as soon as the study was realized.
Amnioscopía:
It is a test that is realized by the end of the pregnancy, from the week 36. He allows to know the state of the baby, from the color of the amniotic liquid. A small metallic pipe interferes with a light, across the neck of the womb.
If the above mentioned device detects the amniotic liquid it is dark, can mean fetal suffering. It usually do this study in case the pregnancy prolongs more normal thing. There exists a possibility, which although it is small, is real: the risk of rupture of the bag of amniotic liquid, or of suffering an amniotic infection.
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