<?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>0300-9041</journal-id>
<journal-title><![CDATA[Ginecología y obstetricia de México]]></journal-title>
<abbrev-journal-title><![CDATA[Ginecol. obstet. Méx.]]></abbrev-journal-title>
<issn>0300-9041</issn>
<publisher>
<publisher-name><![CDATA[Federación Mexicana de Colegios de Obstetricia y Ginecología A.C.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0300-90412017001100763</article-id>
<article-id pub-id-type="doi">10.24245/gom.v85i11.1468</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Bipartición embrionaria temprana: descripción de una serie de 9 casos]]></article-title>
<article-title xml:lang="en"><![CDATA[Early embryo bisection: Nine cases description]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Gómez de Segura Blanco]]></surname>
<given-names><![CDATA[R]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Martínez]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Padilla]]></surname>
<given-names><![CDATA[E]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Moscheta]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Calomarde]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Spies]]></surname>
<given-names><![CDATA[K]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Rayward]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[López-Yañez]]></surname>
<given-names><![CDATA[L]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Izquierdo]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,ProcreaTec Centro Internacional de Reproducción  ]]></institution>
<addr-line><![CDATA[Madrid ]]></addr-line>
<country>España</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,ProcreaTec Centro Internacional de Reproducción  ]]></institution>
<addr-line><![CDATA[Madrid ]]></addr-line>
<country>España</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>00</month>
<year>2017</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>00</month>
<year>2017</year>
</pub-date>
<volume>85</volume>
<numero>11</numero>
<fpage>763</fpage>
<lpage>771</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0300-90412017001100763&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0300-90412017001100763&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0300-90412017001100763&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen  ANTECEDENTES: La tasa de bipartición temprana en concepciones naturales es de 0.4% de los nacimientos. Se ha descrito un aumento de estos casos en tratamientos de reproducción asistida, especialmente durante la transferencia en estadio de blastocisto.  CASO CLÍNICO: se describen nueve casos retrospectivos (2014-2016) de pacientes a quienes se transfirió un embrión y se visualizaron dos sacos, o en las que se transfirieron 2 embriones y se visualizaron 3 sacos. En el periodo de estudio se transfirieron 3737 embriones: 1470 en fresco y 827 desvitrificados. Los 9 casos suponen una tasa de bipartición temprana embrionaria de 0.39% del total de las transferencias y 0.86% del total de los embarazos.  CONCLUSIONES: no existe relación entre el riesgo de división embrionaria y la eclosión (hatching) asistida, ni entre la edad avanzada ovocitaria y la edad paterna. La transferencia de embrión único es la mejor opción en pacientes que reciben ovocitos de donantes jóvenes o participan en protocolos de FIV-ICSI.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstratc  BACKGROUND: The cases in which the embryo divides in two identic embryos is causing real concerns in the treatments of assisted reproduction. The percentage of early bisection in natural conception is about 0.4% on life birth. There is noticed an increase of this cases in treatments of the assisted reproduction, especially when transferring in blastocyst stage.  CASE REPORT:  We have collected series of 9 cases in a retrospective way, between 2014-2016 in which we have transferred 1 embryo and we have visualized 2 sacs, and the cases in which we have transferred 2 embryos and we have visualized 3 sacs. This year we have transferred a total of 3737 embryos, 1470 fresh embryo transfers and 827 frozen embryo transfers. These 9 cases mean the 0.39% of early embryo division and the 0.86% of total of pregnancies.  CONCLUSION: We didn&#8217;t observe a relationship in the risk of embryo division with the hatching. Neither with advanced age of the eggs, non the father&#8217;s age. The rate of division of the embryos in cycles of the assisted reproduction in our clinic using ICSI increase in comparison with the spontaneous gestations, howbeit it would be necessary to do more studies in order to prove this statement. We consider single embryo transfer the best practice in IVF in young women or donor eggs.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[bipartición embrionaria]]></kwd>
<kwd lng="es"><![CDATA[blastocisto]]></kwd>
<kwd lng="es"><![CDATA[transferencia]]></kwd>
<kwd lng="en"><![CDATA[Early bisection]]></kwd>
<kwd lng="en"><![CDATA[Blastocyst]]></kwd>
<kwd lng="en"><![CDATA[Embryo transfer]]></kwd>
</kwd-group>
</article-meta>
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