{"id":111788,"date":"2024-09-24T16:47:37","date_gmt":"2024-09-24T07:47:37","guid":{"rendered":"https:\/\/www.hiro-clinic.or.jp\/nipt\/the-status-of-indeterminate-nipt-cases-at-hiro-clinic-and-measures-to-be-taken\/"},"modified":"2025-08-22T13:46:23","modified_gmt":"2025-08-22T04:46:23","slug":"the-status-of-indeterminate-nipt-cases-at-hiro-clinic-and-measures-to-be-taken","status":"publish","type":"post","link":"https:\/\/www.hiro-clinic.or.jp\/nipt\/the-status-of-indeterminate-nipt-cases-at-hiro-clinic-and-measures-to-be-taken\/?lang=en","title":{"rendered":"Situations and Countermeasures for Inconclusive NIPT Results at Hiro Clinic"},"content":{"rendered":"\n<div style=\"border:solid #ffe6e6 0.8rem;background-color: #fff9f9;padding:3% 5%;margin:1rem 0 3rem;\"><div id=\"ez-toc-container\" class=\"ez-toc-v2_0_84 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">\u76ee\u6b21<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/the-status-of-indeterminate-nipt-cases-at-hiro-clinic-and-measures-to-be-taken\/?lang=en\/#Summary_of_This_Article\" >Summary of This Article<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/the-status-of-indeterminate-nipt-cases-at-hiro-clinic-and-measures-to-be-taken\/?lang=en\/#Proportion_of_Inconclusive_Cases\" >Proportion of Inconclusive Cases<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/the-status-of-indeterminate-nipt-cases-at-hiro-clinic-and-measures-to-be-taken\/?lang=en\/#Main_Causes_of_Inconclusive_Results\" >Main Causes of Inconclusive Results<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/the-status-of-indeterminate-nipt-cases-at-hiro-clinic-and-measures-to-be-taken\/?lang=en\/#Retesting_and_Alternative_Approaches\" >Retesting and Alternative Approaches<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/the-status-of-indeterminate-nipt-cases-at-hiro-clinic-and-measures-to-be-taken\/?lang=en\/#Explanation_and_Response_Strategy\" >Explanation and Response Strategy<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/the-status-of-indeterminate-nipt-cases-at-hiro-clinic-and-measures-to-be-taken\/?lang=en\/#Research_and_Evidence\" >Research and Evidence<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/the-status-of-indeterminate-nipt-cases-at-hiro-clinic-and-measures-to-be-taken\/?lang=en\/#Summary\" >Summary<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<h2 style=\"margin-top:1rem;\"><span class=\"ez-toc-section\" id=\"Summary_of_This_Article\"><\/span>Summary of This Article<span class=\"ez-toc-section-end\"><\/span><\/h2><p><a href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/\">NIPT<\/a> (Non-Invasive Prenatal Testing) is a safe and effective method for accurately detecting chromosomal abnormalities in the fetus. However, there are cases where the test results become inconclusive. At Hiro Clinic as well, a certain number of inconclusive cases have been reported. In the following, we explain in detail the proportion, causes, and countermeasures of such inconclusive cases.<\/p><\/div>\n\n\n\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Proportion_of_Inconclusive_Cases\"><\/span><strong>Proportion of Inconclusive Cases<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Hiro Clinic has not publicly released specific data regarding the percentage of inconclusive results (also known as &#8220;no-call&#8221; results) in their <a href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/\">NIPT<\/a> (Non-Invasive Prenatal Testing). However, on a broader scale, inconclusive results generally occur in <strong>about 1% to 5%<\/strong> of all tests. This percentage can vary depending on the testing method, the technology used, and the testing laboratory. It is assumed that the proportion at Hiro Clinic falls within this range as well.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Main_Causes_of_Inconclusive_Results\"><\/span><strong>Main Causes of Inconclusive Results<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p><strong>1. Maternal Mosaicism<\/strong><strong><br><\/strong> Maternal mosaicism refers to a condition in which different genetic cell lines coexist in the mother\u2019s blood. This mixture of maternal DNA and fetal DNA can blur the genetic signals analyzed during testing, making it difficult to generate a clear result. This is considered one of the primary causes of inconclusive outcomes.<\/p>\n\n\n\n<p><strong>2. Maternal Physiological Variations<\/strong><strong><br><\/strong> Certain physiological or hematological conditions in the mother, such as elevated white blood cell counts or coagulation abnormalities, may interfere with the sequencing process. These irregularities can complicate the interpretation of the DNA fragments and increase the chance of receiving an inconclusive result.<\/p>\n\n\n\n<p><strong>3. Sample Quality Issues<\/strong><strong><br><\/strong> If the blood sample collected is of poor quality \u2014 for example, if the volume is insufficient or the sample degrades during storage or transport \u2014 the DNA may not be suitable for accurate analysis, leading to a no-call result.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Retesting_and_Alternative_Approaches\"><\/span><strong>Retesting and Alternative Approaches<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>Many patients, upon receiving an inconclusive result, opt for <strong>a second blood draw<\/strong>. However, if the underlying cause is maternal mosaicism or a physiological condition, repeating the blood test often yields the same inconclusive result. Hiro Clinic recommends the following strategies in such situations:<\/p>\n\n\n\n<p><strong>1. Amniocentesis<\/strong><strong><br><\/strong> When the <a href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/\">NIPT<\/a> result is inconclusive, <strong>amniocentesis<\/strong> is considered the most reliable follow-up test. This procedure analyzes cells that come directly from the fetus, eliminating interference from maternal DNA and providing a highly accurate result.<br>That said, amniocentesis is an <strong>invasive procedure<\/strong> and carries certain risks, so it requires careful explanation, patient understanding, and informed consent before proceeding.<\/p>\n\n\n\n<p><strong>2. Detailed Explanation and Genetic Counseling<\/strong><strong><br><\/strong> Hiro Clinic offers thorough explanations to patients about the reasons for the inconclusive result. Genetic counseling is emphasized to help patients understand that retesting is not always the best solution. During counseling, the potential influence of maternal mosaicism or physiological variations is clarified, and suitable testing options are discussed.<\/p>\n\n\n\n<p><strong>3. Collaboration with Testing Laboratories<\/strong><strong><br><\/strong> Hiro Clinic works closely with partner laboratories to investigate the specific causes of inconclusive results. This collaboration helps refine testing processes and is expected to reduce the frequency of inconclusive cases over time.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Explanation_and_Response_Strategy\"><\/span><strong>Explanation and Response Strategy<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>At Hiro Clinic, a small proportion of <a href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/\">NIPT<\/a> tests result in inconclusive findings. This is most often due to <strong>maternal mosaicism<\/strong> or <strong>physiological factors<\/strong> that interfere with the analysis. When this happens, simply repeating the blood draw typically does not solve the problem. Instead, amniocentesis is recommended because it directly evaluates fetal cells, ensuring higher accuracy.<br>The clinic provides clear and detailed explanations about the testing process, the associated risks, and the benefits of each option. In parallel, Hiro Clinic continues to strengthen its collaboration with testing facilities, analyzing the underlying factors in each case to minimize future occurrences.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Research_and_Evidence\"><\/span><strong>Research and Evidence<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>Current research shows that inconclusive <a href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/\">NIPT<\/a> results are primarily caused by mixed maternal-fetal DNA signals during sequencing. Advances in laboratory techniques and analytical processes are expected to enhance detection accuracy. Hiro Clinic is actively working to integrate these advancements to make testing more reliable and efficient.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Summary\"><\/span><strong>Summary<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n\n\n\n<p>At Hiro Clinic, inconclusive <a href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/\">NIPT<\/a> results occur in approximately <strong>1% to 5% of cases<\/strong>, mainly due to maternal mosaicism, maternal physiological conditions, or issues with sample quality. Retesting with a second blood draw is <strong>not always effective<\/strong> in resolving these issues. In such situations, amniocentesis is often recommended for more accurate results.<br>By providing comprehensive explanations, offering genetic counseling, and strengthening collaboration with laboratories, Hiro Clinic aims to both improve patient understanding and reduce the occurrence of inconclusive results. For patients, being well-informed and maintaining open communication with their healthcare providers helps ensure that they choose the most appropriate and reliable testing approach.<\/p>\n","protected":false},"excerpt":{"rendered":"Summary of This Arti&#8230;\n <a href=\"https:\/\/www.hiro-clinic.or.jp\/nipt\/the-status-of-indeterminate-nipt-cases-at-hiro-clinic-and-measures-to-be-taken\/?lang=en\">\u7d9a\u304d\u3092\u8aad\u3080<\/a>","protected":false},"author":88,"featured_media":82789,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[97],"tags":[],"class_list":["post-111788","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.hiro-clinic.or.jp\/nipt\/wp-json\/wp\/v2\/posts\/111788","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.hiro-clinic.or.jp\/nipt\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.hiro-clinic.or.jp\/nipt\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.hiro-clinic.or.jp\/nipt\/wp-json\/wp\/v2\/users\/88"}],"replies":[{"embeddable":true,"href":"https:\/\/www.hiro-clinic.or.jp\/nipt\/wp-json\/wp\/v2\/comments?post=111788"}],"version-history":[{"count":3,"href":"https:\/\/www.hiro-clinic.or.jp\/nipt\/wp-json\/wp\/v2\/posts\/111788\/revisions"}],"predecessor-version":[{"id":111804,"href":"https:\/\/www.hiro-clinic.or.jp\/nipt\/wp-json\/wp\/v2\/posts\/111788\/revisions\/111804"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.hiro-clinic.or.jp\/nipt\/wp-json\/wp\/v2\/media\/82789"}],"wp:attachment":[{"href":"https:\/\/www.hiro-clinic.or.jp\/nipt\/wp-json\/wp\/v2\/media?parent=111788"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.hiro-clinic.or.jp\/nipt\/wp-json\/wp\/v2\/categories?post=111788"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.hiro-clinic.or.jp\/nipt\/wp-json\/wp\/v2\/tags?post=111788"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}