{"markup":"\u003C?xml version=\u00221.0\u0022 encoding=\u0022UTF-8\u0022 ?\u003E\n    \u003Chtml version=\u0022HTML+RDFa+MathML 1.1\u0022\n    xmlns:content=\u0022http:\/\/purl.org\/rss\/1.0\/modules\/content\/\u0022\n    xmlns:dc=\u0022http:\/\/purl.org\/dc\/terms\/\u0022\n    xmlns:foaf=\u0022http:\/\/xmlns.com\/foaf\/0.1\/\u0022\n    xmlns:og=\u0022http:\/\/ogp.me\/ns#\u0022\n    xmlns:rdfs=\u0022http:\/\/www.w3.org\/2000\/01\/rdf-schema#\u0022\n    xmlns:sioc=\u0022http:\/\/rdfs.org\/sioc\/ns#\u0022\n    xmlns:sioct=\u0022http:\/\/rdfs.org\/sioc\/types#\u0022\n    xmlns:skos=\u0022http:\/\/www.w3.org\/2004\/02\/skos\/core#\u0022\n    xmlns:xsd=\u0022http:\/\/www.w3.org\/2001\/XMLSchema#\u0022\n    xmlns:mml=\u0022http:\/\/www.w3.org\/1998\/Math\/MathML\u0022\u003E\n  \u003Chead\u003E\u003Cscript type=\u0022text\/javascript\u0022 src=\u0022http:\/\/d282kpwvnogo5m.cloudfront.net\/sites\/default\/files\/js\/js_itu2PgFdrjV-docKmLK8Jn5oXe_05RgvQh73eOhI_mE.js\u0022\u003E\u003C\/script\u003E\n\u003Cscript type=\u0022text\/javascript\u0022 src=\u0022http:\/\/mdc.sagepub.com\/sites\/all\/modules\/highwire\/highwire\/plugins\/highwire_markup_process\/js\/highwire_at_symbol.js?nzp98d\u0022\u003E\u003C\/script\u003E\n\u003Cscript type=\u0022text\/javascript\u0022 src=\u0022http:\/\/mdc.sagepub.com\/sites\/all\/modules\/highwire\/highwire\/plugins\/highwire_markup_process\/js\/highwire_article_reference_popup.js?nzp98d\u0022\u003E\u003C\/script\u003E\n\u003Cscript type=\u0022text\/javascript\u0022 src=\u0022http:\/\/d282kpwvnogo5m.cloudfront.net\/sites\/default\/files\/js\/js_I8yX6RYPZb7AtMcDUA3QKDZqVkvEn35ED11_1i7vVpc.js\u0022\u003E\u003C\/script\u003E\n\u003Cscript type=\u0022text\/javascript\u0022\u003E\n\u003C!--\/\/--\u003E\u003C![CDATA[\/\/\u003E\u003C!--\n(function(i,s,o,g,r,a,m){i[\u0022GoogleAnalyticsObject\u0022]=r;i[r]=i[r]||function(){(i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)})(window,document,\u0022script\u0022,\u0022\/\/www.google-analytics.com\/analytics.js\u0022,\u0022ga\u0022);ga(\u0022create\u0022, \u0022UA-15605596-27\u0022, {\u0022cookieDomain\u0022:\u0022auto\u0022});ga(\u0022set\u0022, \u0022page\u0022, location.pathname + location.search + location.hash);ga(\u0022send\u0022, \u0022pageview\u0022);ga(\u0027create\u0027, \u0027UA-189672-26\u0027, \u0027auto\u0027, {\u0027name\u0027: \u0027hwTracker\u0027});\r\nga(\u0027hwTracker.send\u0027, \u0027pageview\u0027);\n\/\/--\u003E\u003C!]]\u003E\n\u003C\/script\u003E\n\u003Cscript type=\u0022text\/javascript\u0022\u003E\n\u003C!--\/\/--\u003E\u003C![CDATA[\/\/\u003E\u003C!--\njQuery.extend(Drupal.settings, {\u0022basePath\u0022:\u0022\\\/\u0022,\u0022pathPrefix\u0022:\u0022\u0022,\u0022highwire\u0022:{\u0022markup\u0022:[{\u0022requested\u0022:\u0022full-text\u0022,\u0022variant\u0022:\u0022full-text\u0022,\u0022view\u0022:\u0022full\u0022,\u0022pisa\u0022:\u0022spmdc;14\\\/7\\\/17-a\u0022},{\u0022requested\u0022:\u0022long\u0022,\u0022variant\u0022:\u0022full-text\u0022,\u0022view\u0022:\u0022full\u0022,\u0022pisa\u0022:\u0022spmdc;14\\\/7\\\/17-a\u0022}],\u0022ac\u0022:{\u0022spmdc;14\\\/7\\\/17-a\u0022:{\u0022access\u0022:{\u0022reprint\u0022:true,\u0022full\u0022:true},\u0022pisa_id\u0022:\u0022spmdc;14\\\/7\\\/17-a\u0022,\u0022atom_uri\u0022:\u0022\u0022,\u0022jcode\u0022:\u0022spmdc\u0022}}},\u0022googleanalytics\u0022:{\u0022trackOutbound\u0022:1,\u0022trackMailto\u0022:1,\u0022trackDownload\u0022:1,\u0022trackDownloadExtensions\u0022:\u00227z|aac|arc|arj|asf|asx|avi|bin|csv|doc(x|m)?|dot(x|m)?|exe|flv|gif|gz|gzip|hqx|jar|jpe?g|js|mp(2|3|4|e?g)|mov(ie)?|msi|msp|pdf|phps|png|ppt(x|m)?|pot(x|m)?|pps(x|m)?|ppam|sld(x|m)?|thmx|qtm?|ra(m|r)?|sea|sit|tar|tgz|torrent|txt|wav|wma|wmv|wpd|xls(x|m|b)?|xlt(x|m)|xlam|xml|z|zip\u0022,\u0022trackUrlFragments\u0022:1},\u0022ajaxPageState\u0022:{\u0022js\u0022:{\u0022sites\\\/all\\\/libraries\\\/cluetip\\\/jquery.cluetip.js\u0022:1,\u0022sites\\\/all\\\/libraries\\\/cluetip\\\/lib\\\/jquery.hoverIntent.js\u0022:1,\u0022sites\\\/all\\\/libraries\\\/cluetip\\\/lib\\\/jquery.bgiframe.min.js\u0022:1,\u0022sites\\\/all\\\/modules\\\/highwire\\\/highwire\\\/plugins\\\/highwire_markup_process\\\/js\\\/highwire_at_symbol.js\u0022:1,\u0022sites\\\/all\\\/modules\\\/highwire\\\/highwire\\\/plugins\\\/highwire_markup_process\\\/js\\\/highwire_article_reference_popup.js\u0022:1,\u0022sites\\\/all\\\/modules\\\/contrib\\\/google_analytics\\\/googleanalytics.js\u0022:1,\u00220\u0022:1}}});\n\/\/--\u003E\u003C!]]\u003E\n\u003C\/script\u003E\n\u003Clink type=\u0022text\/css\u0022 rel=\u0022stylesheet\u0022 href=\u0022\/\/d282kpwvnogo5m.cloudfront.net\/sites\/default\/files\/cdn\/css\/http\/css_Xg7z6oCTVgud_Q0huYz9x9iiD5H_2YPSJ5z2ZViSWdY.css\u0022 media=\u0022all\u0022 \/\u003E\n\u003Clink rel=\u0027stylesheet\u0027 type=\u0027text\/css\u0027 href=\u0027\/sites\/all\/modules\/contrib\/panels\/plugins\/layouts\/onecol\/onecol.css\u0027 \/\u003E\u003C\/head\u003E\u003Cbody\u003E\u003Cdiv class=\u0022panels-ajax-tab-panel panels-ajax-tab-panel-sageoa-tab-art\u0022\u003E\u003Cdiv class=\u0022panel-display panel-1col clearfix\u0022 \u003E\n  \u003Cdiv class=\u0022panel-panel panel-col\u0022\u003E\n    \u003Cdiv\u003E\u003Cdiv class=\u0022panel-pane pane-highwire-markup\u0022 \u003E\n  \n      \n  \n  \u003Cdiv class=\u0022pane-content\u0022\u003E\n    \u003Cdiv class=\u0022highwire-markup\u0022\u003E\u003Cdiv xmlns=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022 id=\u0022content-block-markup\u0022 xmlns:xhtml=\u0022http:\/\/www.w3.org\/1999\/xhtml\u0022\u003E\u003Cdiv class=\u0022article fulltext-view \u0022\u003E\u003Cspan class=\u0022highwire-journal-article-marker-start\u0022\u003E\u003C\/span\u003E\u003Cdiv class=\u0022section abstract\u0022 id=\u0022abstract-1\u0022\u003E\u003Ch2\u003ESummary\u003C\/h2\u003E\n            \u003Cp id=\u0022p-1\u0022\u003EThis article presents results from an 11-year study showing an increased incidence of monozygotic twin pregnancies over the past decade in association with the use of assisted reproductive technology (ART) [Kanter JR et al. \u003Cem\u003EObstet Gynecol\u003C\/em\u003E 2014]. Results also showed that Day 5 embryo transfer and assisted embryo hatching are associated with an increased risk of monozygotic twinning.\u003C\/p\u003E\n         \u003C\/div\u003E\u003Cul class=\u0022kwd-group\u0022\u003E\u003Cli class=\u0022kwd\u0022\u003EPregnancy\u003C\/li\u003E\u003Cli class=\u0022kwd\u0022\u003EDiagnostic \u0026amp; Surgical Procedures\u003C\/li\u003E\u003Cli class=\u0022kwd\u0022\u003EInfertility Clinical Trials\u003C\/li\u003E\u003C\/ul\u003E\u003Cul class=\u0022kwd-group clinical-trial\u0022\u003E\u003Cli class=\u0022kwd\u0022\u003EPregnancy\u003C\/li\u003E\u003Cli class=\u0022kwd\u0022\u003EDiagnostic \u0026amp; Surgical Procedures\u003C\/li\u003E\u003Cli class=\u0022kwd\u0022\u003EInfertility\u003C\/li\u003E\u003Cli class=\u0022kwd\u0022\u003EObstetrics \u0026amp; Gynecology\u003C\/li\u003E\u003Cli class=\u0022kwd\u0022\u003EObstetrics \u0026amp; Gynecology Clinical Trials\u003C\/li\u003E\u003C\/ul\u003E\u003Cp id=\u0022p-2\u0022\u003EJessica R. Kanter, BS, Emory University, Decatur, Georgia, USA, presented results from an 11-year study showing an increased incidence of monozygotic twin pregnancies over the past decade in association with the use of assisted reproductive technology (ART) [Kanter IR et al. \u003Cem\u003EObstet Gynecol\u003C\/em\u003E 2014]. Results also showed that Day 5 embryo transfer and assisted embryo hatching are associated with an increased risk of monozygotic twinning.\u003C\/p\u003E\u003Cp id=\u0022p-3\u0022\u003EThe use of ART has increased dramatically in recent decades, making pregnancy possible for many infertile couples. However, the use of ART has also been associated with a marked rise in the rate of multiple births in the United States, with the incidence of twin births almost doubling from 1971 through 2009 [Kulkarni AD et al. \u003Cem\u003EN Engl J Med\u003C\/em\u003E 2013].\u003C\/p\u003E\u003Cp id=\u0022p-4\u0022\u003EWhen compared with that of traditional fertility, monozygotic twinning is more common after infertility treatment; however, very little is known about the mechanisms involved or the factors contributing to its occurrence. Kanter and colleagues conducted a large population-based surveillance study to examine trends of monozygotic twinning in ART and to determine its association with transfer factors.\u003C\/p\u003E\u003Cp id=\u0022p-5\u0022\u003EThe study included 392 136 pregnancies resulting from fresh nondonor embryo transfers that were reported to the Centers for Disease Control and Prevention\u0027s National ART Surveillance System between 2000 and 2011.\u003C\/p\u003E\u003Cp id=\u0022p-6\u0022\u003EData were evaluated to examine trends of monozygotic twin pregnancies, defined as those in which the number of fetal heart tones on first-trimester ultrasound exceeded the number of embryos transferred. The results were subsequently compared with data for singleton pregnancies (1 fetal heart tone present) and other multiple-gestation pregnancies (\u0026gt;1 fetal heart tone present but not more than number of embryos transferred). Adjusted risk ratios (ARRs) were calculated for monozygotic twinning in association with assisted embryo hatching for singleton and other multiple-gestation pregnancies.\u003C\/p\u003E\u003Cp id=\u0022p-7\u0022\u003EThe results showed a significant increase in the incidence of monozygotic twinning after ART from 2000 through 2011 (p\u0026lt;0.001), with a higher incidence in Day 5 embryo transfers compared with Day 3 (1.72% vs 0.48%).\u003C\/p\u003E\u003Cp id=\u0022p-8\u0022\u003EMonozygotic twinning was associated with assisted hatching among Day 3 embryo transfers with singleton pregnancies (ARR, 2.19; 95% CI, 1.93 to 2.48) and other multiple-gestation pregnancies (ARR, 2.27; 95% CI, 2.00 to 2.57) and among Day 5 embryo transfers when compared with other multiple-gestation pregnancies (ARR, 1.18; 95% CI, 1.05 to 1.32).\u003C\/p\u003E\u003Cp id=\u0022p-9\u0022\u003EThe results show an increased incidence of monozygotic twin pregnancies after ART over the past decade. They also show that Day 5 transfer and assisted hatching are associated with an increased risk of monozygotic twinning.\u003C\/p\u003E\u003Cp id=\u0022p-10\u0022\u003EKanter concluded that the rising incidence of monozygotic twinning in association with ART warrants a closer look. Prospective trials are still needed.\u003C\/p\u003E\u003Cul class=\u0022copyright-statement\u0022\u003E\u003Cli class=\u0022fn\u0022 id=\u0022copyright-statement-1\u0022\u003E\u00a9 2014 MD Conference Express\u00ae\u003C\/li\u003E\u003C\/ul\u003E\u003Cspan class=\u0022highwire-journal-article-marker-end\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003Cspan id=\u0022related-urls\u0022\u003E\u003C\/span\u003E\u003C\/div\u003E\u003Ca href=\u0022http:\/\/mdc.sagepub.com\/content\/14\/7\/17.1.abstract\u0022 class=\u0022hw-link hw-link-article-abstract\u0022 data-icon-position=\u0022\u0022 data-hide-link-title=\u00220\u0022\u003EView Summary\u003C\/a\u003E\u003C\/div\u003E  \u003C\/div\u003E\n\n  \n  \u003C\/div\u003E\n\u003C\/div\u003E\n  \u003C\/div\u003E\n\u003C\/div\u003E\n\u003C\/div\u003E\u003Cscript type=\u0022text\/javascript\u0022 src=\u0022http:\/\/mdc.sagepub.com\/sites\/all\/modules\/highwire\/highwire\/plugins\/highwire_markup_process\/js\/highwire_openurl.js?nzp98d\u0022\u003E\u003C\/script\u003E\n\u003C\/body\u003E\u003C\/html\u003E"}