Prenatal Diagnostics

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Prenatal diagnostics
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The prenatal diagnostics are tests that are performed on a fetus or embryo before it is born to identify if they have a genetic deficiency or genetic mutation which can unleash a genetic disease. The screening can also be used for prenatal sex discernment. There are two types ofprenatal diagnostic, invasive or non invasive for the fetus.
The non invasive tests are process that involves no instruments that physically enter the body and are made to control a good development of the fetus during the pregnancy stage. Those tests are:
Ultrasound: Performed three, one each trimester and with that we can see the evolution of the baby. It is for fetal assessment and diagnosis ofanomalies. This method is based on the use of ultrasound to create two-dimensional or three-dimensional images.

Weight: is a rarely factor that could harm the baby and the normal increase of a pregnant is between 10 and 15 kilograms.
Blood pressure: a high blood pressure can be dangerous and hazardous to the evolution of the pregnancy as a low pressure.Uranalysis: it is useful to detect bacteria or other signs of illness.
Blood analysis: it control the number of red blood cells and the iron content of the blood. Also with the blood of the mother we can determinate the blood type and the Rh factor of the child. As well with this test we can know if the baby has some disease like rubella or some select trisomies ( down syndrome in U.S.A, and Down andEdwards syndromes in china)
The invasive techniques are those who take some risk for the fetus like chorionic villus sampling (CVS) and amniocentesis. This two are the most common but exist more of them. Also those tests are the most criticized because the risk to lost the fetus, and for the ethical issues that it involves, like what it´s the value of mentally or physically disabled people inthe society.
Amniocentesis: it´s also referred to as amniotic fluid test. It`s a medical procedure used in diagnosis of chromosomal abnormalities and fetal infections. It is performed between the 15th and 20th week of pregnancy; performing this test earlier may result in fetal injury. The procedure of this technique is based on a puncture in the pregnant woman's belly with which and with the helpof a needle is obtained amniotic fluid, which is in contact with the fetus and therefore has his cell. This puncture is performed with the aid of an ultrasound machine to avoid as far as possible to damage the fetus as seen in the image. The puncture usually hurts so local anesthesia is administered to the mother.
Of the liquid obtained in the puncture are separated the fetal cells. These cellsgrow in a culture medium, then fixed and stained. Under microscope the chromosomes are examined individually for any abnormalities, the most commonly found are trisomies such as trisomy 21 (Down syndrome) or trisomy 18 (Edward syndrome). In regard to the fetus the puncture heals and the liquid is replaced in the next few days.
Chorionic Villus Sampling: It is a form of prenatal diagnosis todetermine chromosomal or genetic disorders in the fetus. It is done between the 11th and 13th week of gestation. And it is based on the extraction of fetal tissue. It can be performed through the cervix (trancervical) or through the belly (transabdominal). Spontaneous abortion rates are slightly higher when the test is done through the cervix.
The procedure is based on the insertion of a thin plastictube through the vagina and cervix to reach the amniotic fluid. To prevent damage to the fetus is done with the help of ultrasound to guide the tube to the best area and then removes a small sample of chorionic villus tissue. The sample obtained is growing in a culture medium for approximately 2 weeks and evaluated in the lab as in amniocentesis.
This tests can detected more than 200 disorders,...