<?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>S0300-90412020000500306</article-id>
<article-id pub-id-type="doi">10.24245/gom.v88i5.3935</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Evaluación de la tasa de blastocistos euploides en fase folicular y lútea (DuoStim) en mujeres con pobre respuesta ovárica: estudio preliminar en México]]></article-title>
<article-title xml:lang="en"><![CDATA[Euploid blastocyst rate in follicular vs luteal phase (DuoStim) in women with poor ovarian response: Preliminary study in Mexico]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Barroso-Villa]]></surname>
<given-names><![CDATA[Gerardo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
<xref ref-type="aff" rid="Aaf"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Valdespin-Fierro]]></surname>
<given-names><![CDATA[Carlos]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
<xref ref-type="aff" rid="Aaf"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[García-Montes]]></surname>
<given-names><![CDATA[Lucía]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Weiser-Smeke]]></surname>
<given-names><![CDATA[Ariane]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Machargo-Gordillo]]></surname>
<given-names><![CDATA[Ana]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ávila-Lombardo]]></surname>
<given-names><![CDATA[Rosaura]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,NASCERE Centro de Reproducción Arcos ]]></institution>
<addr-line><![CDATA[Ciudad de México ]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Centro Médico ABC departamento de Ginecología y Obstetricia ]]></institution>
<addr-line><![CDATA[Ciudad de México ]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,NASCERE Centro de Reproducción Arcos ]]></institution>
<addr-line><![CDATA[Ciudad de México ]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af4">
<institution><![CDATA[,NASCERE Centro de Reproducción Arcos ]]></institution>
<addr-line><![CDATA[Ciudad de México ]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>00</month>
<year>2020</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>00</month>
<year>2020</year>
</pub-date>
<volume>88</volume>
<numero>5</numero>
<fpage>306</fpage>
<lpage>311</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0300-90412020000500306&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0300-90412020000500306&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0300-90412020000500306&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen:  OBJETIVO: Comparar la tasa de blastocistos euploides obtenida después de la estimulación ovárica en fase folicular con la fase lútea en un mismo ciclo menstrual en pacientes con deficiente respuesta ovárica.  MATERIALES Y MÉTODOS:  Estudio clínico, prospectivo y comparativo llevado a cabo en el Centro de Reproducción Arcos, Nascere, entre los meses de enero a julio de 2019. Se incluyeron pacientes con pobre respuesta ovárica según los criterios de Bologna y con indicación de PGT-A. Las estimulaciones en fase folicular y lútea se efectuaron con antagonista de la GnRH y FSHr/LHr (2:1) a partir del día 3 del ciclo y 5 días después de la primera recuperación de los ovocitos. Para completar el proceso de maduración ovocitaria se utilizaron análogos de GnRH, se tomó una biopsia de trofoectodermo en día 5-7.  RESULTADOS: Se estudiaron 20 pacientes. Al comparar la fase folicular con la lútea la tasa de fertilización fue de 79% (IC95%: 29-46) vs 55% (IC95%: 34-53), la tasa de blastocistos 42% (IC95%: 19-44) vs 45% (IC95%: 24-55) y la tasa de blastocistos euploides 100% (IC95%: 44-53) vs 70% (IC95%: 38-46), respectivamente. Solo la tasa de recuperación de ovocitos en metafase II mostró diferencias significativas entre ambas fases 40% (IC95%: 18-37) vs 59% (IC95%: 31-59), p = 0.0333 en la fase folicular y lútea, respectivamente.  CONCLUSIONES: La estimulación ovárica bifásica (folicular-lútea), en el mismo ciclo menstrual (DuoStim), resultó en mayor tasa de recuperación de ovocitos en metafase II durante la fase lútea. Sin embargo, las tasas de desarrollo embrionario a día 5-6 (blastocistos) y de embriones euploides fueron similares entre ambas fases.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract:  OBJECTIVE: Euploid blastocyst rate comparison between ovarian stimulation in follicular vs luteal phase performed in the same menstrual cycle in patients with poor ovarian response.  MATERIALS AND METHODS:  Clinical, prospective and comparative study conducted at Centro de Reproducción Arcos S.C., &#8220;Nascere&#8221;, during january-july, 2019. Patients with PGT-A indication and poor ovarian response according to Bologna criteria were included. Under a short GnRH-antagonist protocol, stimulations, both in follicular and luteal phase were performed using rFSH/rLH (2:1) from day 3 of the cycle and 5 days after the first oocyte retrieval. In addition, ovulation trigger with an GnRH agonist was used, finally, on day 5-6 of embryo development, trophoctoctoderm biopsy was performed.  RESULTS: In this study, 20 patients were included; when comparing follicular phase vs luteal phase, we found that fertilization rate was 79% (95%CI 29-46) vs 55% (95%CI 34-53), blastocysts rate was 42% (95%CI 19-44) vs 45% (95%CI 24-55) and euploid embryo rate was 100% (95%CI 44-53) vs 70% (95%CI 38-46). Only the oocyte recovery rate in metaphase II showed significant differences between both phases 40% (IC 95% 18-37) vs 59% (IC 95% 31-59), p=0.0333.  CONCLUSION:  Biphasic ovarian stimulation (follicular/ luteal) in the same menstrual cycle (DuoStim) resulted in a higher metaphase II ooctye recovery rate during the luteal phase in comparison with the follicular phase. However, the rates of blastocysts and euploid blastocysts were similar between both phases.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Blastocisto]]></kwd>
<kwd lng="es"><![CDATA[estimulación ovárica]]></kwd>
<kwd lng="es"><![CDATA[fase lútea]]></kwd>
<kwd lng="es"><![CDATA[ciclo menstrual]]></kwd>
<kwd lng="es"><![CDATA[fase folicular]]></kwd>
<kwd lng="es"><![CDATA[recuperación de ovocitos]]></kwd>
<kwd lng="es"><![CDATA[metafase]]></kwd>
<kwd lng="es"><![CDATA[inducción de la ovulación]]></kwd>
<kwd lng="en"><![CDATA[Blastocyst]]></kwd>
<kwd lng="en"><![CDATA[Ovarian stimulation]]></kwd>
<kwd lng="en"><![CDATA[Luteal phase]]></kwd>
<kwd lng="en"><![CDATA[Menstrual cycle]]></kwd>
<kwd lng="en"><![CDATA[Follicular phase]]></kwd>
<kwd lng="en"><![CDATA[Oocyte retrieval]]></kwd>
<kwd lng="en"><![CDATA[Metaphase]]></kwd>
<kwd lng="en"><![CDATA[Ovulation induction]]></kwd>
</kwd-group>
</article-meta>
</front><back>
<ref-list>
<ref id="B1">
<label>1</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Baerwald]]></surname>
<given-names><![CDATA[AR]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[A new model for ovarian follicular development during the human menstrual cycle]]></article-title>
<source><![CDATA[Fertil Steril]]></source>
<year>2003</year>
<volume>80</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>116-22</page-range></nlm-citation>
</ref>
<ref id="B2">
<label>2</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Baerwald]]></surname>
<given-names><![CDATA[AR]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Ovarian antral folliculogenesis during the human menstrual cycle: a review]]></article-title>
<source><![CDATA[Hum Reprod Update]]></source>
<year>2012</year>
<volume>18</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>73-91</page-range></nlm-citation>
</ref>
<ref id="B3">
<label>3</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[De Mello Bianchi]]></surname>
<given-names><![CDATA[PH]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Review: follicular waves in the human ovary: a new physiological paradigm for novel ovarian stimulation protocols]]></article-title>
<source><![CDATA[Reprod Sci]]></source>
<year>2010</year>
<volume>17</volume>
<numero>12</numero>
<issue>12</issue>
<page-range>1067-76</page-range></nlm-citation>
</ref>
<ref id="B4">
<label>4</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Baerwald]]></surname>
<given-names><![CDATA[AR]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Characterization of ovarian follicular wave dynamics in women]]></article-title>
<source><![CDATA[Biol Reprod]]></source>
<year>2003</year>
<volume>69</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>1023-31</page-range></nlm-citation>
</ref>
<ref id="B5">
<label>5</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Kuang]]></surname>
<given-names><![CDATA[Y]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Luteal-phase ovarian stimulation case report: three-year follow-up of a twin birth]]></article-title>
<source><![CDATA[J IVF Reprod Med Genet]]></source>
<year>2013</year>
<volume>1</volume>
<numero>106</numero>
<issue>106</issue>
</nlm-citation>
</ref>
<ref id="B6">
<label>6</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Bentov]]></surname>
<given-names><![CDATA[Y]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[An ongoing pregnancy from two waves of follicles developing during a long follicular phase of the same cycle]]></article-title>
<source><![CDATA[Fertil Steril]]></source>
<year>2010</year>
<volume>94</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>350.e8-11</page-range></nlm-citation>
</ref>
<ref id="B7">
<label>7</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Martínez]]></surname>
<given-names><![CDATA[F]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Comparison of starting ovarian stimulation on day 2 versus day 15 of the menstrual cycle in the same oocyte donor and pregnancy rates among the corresponding recipients of vitrified oocytes]]></article-title>
<source><![CDATA[Fertil Steril]]></source>
<year>2014</year>
<volume>102</volume>
<numero>5</numero>
<issue>5</issue>
<page-range>1307-11</page-range></nlm-citation>
</ref>
<ref id="B8">
<label>8</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Ubaldi]]></surname>
<given-names><![CDATA[FM]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Follicular versus luteal phase ovarian stimulation during the same menstrual cycle (DuoStim) in a reduced ovarian reserve population results in a similar euploid blastocyst formation rate: new insight in ovarian reserve exploitation]]></article-title>
<source><![CDATA[Fertil Steril]]></source>
<year>2016</year>
<volume>105</volume>
<numero>6</numero>
<issue>6</issue>
<page-range>1488-95.e1</page-range></nlm-citation>
</ref>
<ref id="B9">
<label>9</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Kuwayama]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Highly efficient vitrification method for cryopreservation of human oocytes]]></article-title>
<source><![CDATA[Reprod Biomed Online]]></source>
<year>2005</year>
<volume>11</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>300-8</page-range></nlm-citation>
</ref>
<ref id="B10">
<label>10</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Ferraretti]]></surname>
<given-names><![CDATA[AP]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[ESHRE consensus on the definition of poor response to ovarian stimulation for in vitro fertilization: The Bologna criteria]]></article-title>
<source><![CDATA[Huma Reprod]]></source>
<year>2011</year>
<volume>26</volume>
<numero>7</numero>
<issue>7</issue>
<page-range>1616-24</page-range></nlm-citation>
</ref>
<ref id="B11">
<label>11</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Ubaldi]]></surname>
<given-names><![CDATA[F]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Management of poor responders in IVF: is there anything new?]]></article-title>
<source><![CDATA[Biomed Res Int]]></source>
<year>2014</year>
<page-range>352098</page-range></nlm-citation>
</ref>
<ref id="B12">
<label>12</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Tsampras]]></surname>
<given-names><![CDATA[N]]></given-names>
</name>
<name>
<surname><![CDATA[Gould]]></surname>
<given-names><![CDATA[D]]></given-names>
</name>
<name>
<surname><![CDATA[Fitzgerald]]></surname>
<given-names><![CDATA[CT.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Double ovarian stimulation (DuoStim) protocol for fertility preservation in female oncology patients]]></article-title>
<source><![CDATA[Hum Fertil (Camb)]]></source>
<year>2017</year>
<volume>20</volume>
<numero>4</numero>
<issue>4</issue>
<page-range>248-53</page-range></nlm-citation>
</ref>
<ref id="B13">
<label>13</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[La Marca]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
<name>
<surname><![CDATA[Sunkara]]></surname>
<given-names><![CDATA[SK.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Individualization of controlled ovarian stimulation in IVF using ovarian reserve markers: From theory to practice]]></article-title>
<source><![CDATA[Hum Reprod Update]]></source>
<year>2014</year>
<volume>20</volume>
<page-range>124-40</page-range></nlm-citation>
</ref>
<ref id="B14">
<label>14</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[L.]]></surname>
<given-names><![CDATA[Hu]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Comparison of different ovarian hyperstimulation protocols efficacy in poor ovarian responders according to the Bologna criteria]]></article-title>
<source><![CDATA[Int J Clin Exp Med]]></source>
<year>2014</year>
<volume>7</volume>
<page-range>1128-34</page-range></nlm-citation>
</ref>
<ref id="B15">
<label>15</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Lin]]></surname>
<given-names><![CDATA[LT]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Luteal Phase Ovarian Stimulation May Improve Oocyte Retrieval and Oocyte Quality in Poor Ovarian Responders Undergoing In Vitro Fertilization: Preliminary Results from a Single-Center Prospective Pilot Study]]></article-title>
<source><![CDATA[Adv Ther]]></source>
<year>2018</year>
<volume>35</volume>
<numero>6</numero>
<issue>6</issue>
<page-range>847-56</page-range></nlm-citation>
</ref>
<ref id="B16">
<label>16</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Vaiarelli]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Double Stimulation in the Same Ovarian Cycle (DuoStim) to Maximize the Number of Oocytes Retrieved from Poor Prognosis Patients: A Multicenter Experience and SWOT Analysis]]></article-title>
<source><![CDATA[Frontiers in Endocrinology]]></source>
<year>2018</year>
<volume>14</volume>
<numero>9</numero>
<issue>9</issue>
<page-range>317</page-range></nlm-citation>
</ref>
<ref id="B17">
<label>17</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Wang]]></surname>
<given-names><![CDATA[N]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Luteal-phase ovarian stimulation vs conventional ovarian stimulation in patients with normal ovarian reserve treated for IVF: a large retrospective cohort study]]></article-title>
<source><![CDATA[Clin Endocrinol (Oxf)]]></source>
<year>2016</year>
<volume>84</volume>
<numero>5</numero>
<issue>5</issue>
<page-range>720-8</page-range></nlm-citation>
</ref>
<ref id="B18">
<label>18</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Lin]]></surname>
<given-names><![CDATA[LT]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The use of luteal-phase ovarian stimulation for poor ovarian responders undergoing in vitro fertilization/intracytoplasmic sperm injection-embryo transfer treatment]]></article-title>
<source><![CDATA[Taiwanese Journal of Obstetrics and Gynecology]]></source>
<year>2016</year>
<volume>55</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>307-8</page-range></nlm-citation>
</ref>
<ref id="B19">
<label>19</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Moffat]]></surname>
<given-names><![CDATA[R]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Dual ovarian stimulation is a new viable option for enhancing the oocyte yield when the time for assisted reproductive technology is limited]]></article-title>
<source><![CDATA[Reprod Biomed Online]]></source>
<year>2014</year>
<volume>29</volume>
<page-range>659-61</page-range></nlm-citation>
</ref>
<ref id="B20">
<label>20</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Cakmak]]></surname>
<given-names><![CDATA[H]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Effective method for emergency fertility preservation: random-start controlled ovarian stimulation]]></article-title>
<source><![CDATA[Fertil Steril]]></source>
<year>2013</year>
<volume>100</volume>
<numero>6</numero>
<issue>6</issue>
<page-range>1673-80</page-range></nlm-citation>
</ref>
<ref id="B21">
<label>21</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Kuang]]></surname>
<given-names><![CDATA[Y]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Double stimulations during the follicular and luteal phases of poor responders in IVF/ICSI programmes (Shanghai protocol)]]></article-title>
<source><![CDATA[Reproductive biomedicine online]]></source>
<year>2014</year>
<volume>29</volume>
<numero>6</numero>
<issue>6</issue>
<page-range>684-91</page-range></nlm-citation>
</ref>
<ref id="B22">
<label>22</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Cimadomo]]></surname>
<given-names><![CDATA[D]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Luteal phase anovulatory follicles result in the production of competent oocytes: intra-patient paired case-control study comparing follicular versus luteal phase stimulations in the same ovarian cycle]]></article-title>
<source><![CDATA[Hum Repro]]></source>
<year>2018</year>
</nlm-citation>
</ref>
</ref-list>
</back>
</article>
