<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>1561-3194</journal-id>
<journal-title><![CDATA[Revista de Ciencias Médicas de Pinar del Río]]></journal-title>
<abbrev-journal-title><![CDATA[Rev Ciencias Médicas]]></abbrev-journal-title>
<issn>1561-3194</issn>
<publisher>
<publisher-name><![CDATA[Editorial Ciencias Médicas]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1561-31942023000700036</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Métodos para el diagnóstico prenatal precoz del síndrome de Down]]></article-title>
<article-title xml:lang="en"><![CDATA[Methods for early prenatal diagnosis of Down's syndrome]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Viteri Rodríguez]]></surname>
<given-names><![CDATA[Juan Alberto]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[López Barrionuevo]]></surname>
<given-names><![CDATA[Carlos Gustavo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Arellano Oleas]]></surname>
<given-names><![CDATA[Yesenia Esthefanía]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Regional Autónoma de Los Andes  ]]></institution>
<addr-line><![CDATA[Ambato ]]></addr-line>
<country>Ecuador</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2023</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2023</year>
</pub-date>
<volume>27</volume>
<numero>6</numero>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_arttext&amp;pid=S1561-31942023000700036&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_abstract&amp;pid=S1561-31942023000700036&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_pdf&amp;pid=S1561-31942023000700036&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[RESUMEN El síndrome de Down es un trastorno genético causado por la trisomía del cromosoma 21. Es una de las enfermedades genéticas más comunes y está asociada con discapacidad intelectual y del desarrollo. Con el objetivo de describir los métodos para el diagnóstico precoz del síndrome de Down se desarrolló el presente artículo. La esperanza de vida de los pacientes con síndrome de Down ha aumentado en los últimos años y su prevalencia en el Ecuador es mayor que a nivel mundial. Se destaca que el diagnóstico prenatal temprano del síndrome de Down se logra con pruebas no invasivas, pero se necesita una prueba invasiva para confirmarlo. La translucencia nucal es el mejor marcador ecográfico para detectar el síndrome de Down. La proteína A plasmática es el marcador con mayor capacidad discriminatoria en el primer trimestre de gestación, y las pruebas de diagnóstico invasivas como la amniocentesis y la biopsia de microvellosidades implican riesgos para la madre y el feto y se recomienda su uso solo en casos de riesgo previo para confirmar el síndrome.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT Down syndrome is a genetic disorder caused by trisomy of chromosome 21. It is one of the most common genetic diseases and is associated with intellectual and developmental disability. The present article was developed to describe methods for early diagnosis of Down syndrome. The life expectancy of patients with Down syndrome has increased in recent years and its prevalence in Ecuador is higher than worldwide. It is emphasized that early prenatal diagnosis of Down syndrome is achieved with noninvasive tests, but an invasive test is needed to confirm it. Nuchal translucency is the best ultrasound marker to detect Down syndrome. Plasma protein A is the marker with the highest discriminatory capacity in the first trimester of gestation, and invasive diagnostic tests such as amniocentesis and microvillus biopsy involve risks for the mother and fetus and their use is recommended only in cases of previous risk to confirm the syndrome.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[SÍNDROME DE DOWN]]></kwd>
<kwd lng="es"><![CDATA[DIAGNÓSTICO PRENATAL]]></kwd>
<kwd lng="es"><![CDATA[ENFERMEDADES GENÉTICAS CONGÉNITAS]]></kwd>
<kwd lng="es"><![CDATA[TÉCNICAS Y PROCEDIMIENTOS DIAGNÓSTICOS]]></kwd>
<kwd lng="en"><![CDATA[DOWN SYNDROME]]></kwd>
<kwd lng="en"><![CDATA[PRENATAL DIAGNOSIS]]></kwd>
<kwd lng="en"><![CDATA[GENETIC DISEASES, INBORN]]></kwd>
<kwd lng="en"><![CDATA[DIAGNOSTIC TECHNIQUES AND PROCEDURES]]></kwd>
</kwd-group>
</article-meta>
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<page-range>1227-36</page-range></nlm-citation>
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<label>19</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Saller]]></surname>
<given-names><![CDATA[D]]></given-names>
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<name>
<surname><![CDATA[Canick]]></surname>
<given-names><![CDATA[JA.]]></given-names>
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</person-group>
<article-title xml:lang=""><![CDATA[Current Methods of Prenatal Screening for Down Syndrome and Other Fetal Abnormalities.]]></article-title>
<source><![CDATA[Clin Obstet Gynecol]]></source>
<year>2008</year>
<volume>51</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>24-36</page-range></nlm-citation>
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</article>
