{"id":82,"date":"2026-09-04T08:02:26","date_gmt":"2026-09-04T08:02:26","guid":{"rendered":"https:\/\/ivfprep.guide\/articles\/signs-of-fertilization\/"},"modified":"2026-09-26T08:21:35","modified_gmt":"2026-09-26T08:21:35","slug":"signs-of-fertilization","status":"publish","type":"post","link":"https:\/\/ivfprep.guide\/articles\/signs-of-fertilization\/","title":{"rendered":"Can You Feel Fertilisation After a Transfer?"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\"><strong>No. In an IVF cycle fertilisation happens in a laboratory dish, days before your transfer, so there is nothing left to fertilise by the time an embryo is placed back and nothing in your body to feel. Your clinic already told you the fertilisation result by telephone. 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it, why the general pregnancy articles describe a different first week, what the laboratory tells you at each call, and what the twinges after a transfer can and cannot be traced to.<\/p>\n\n\n\n<div class=\"msq\" id=\"ms-quiz\" data-slug=\"signs-of-fertilization\" data-category=\"the two week wait\" data-list=\"1\">\n<style>.msq,.msq-hook,.msq-box,.msq-end,.msq-tool{--msq-accent:#1F4E79;--msq-accent-text:#FFFFFF;--msq-line:#CBD8E6;--msq-warn:#B4531A;--msq-muted:#4A5560;--msq-tint:#EEF3F8;--msq-base:#FFFFFF}\n.msq{margin:1.25em 0 1.75em}\n.msq-hook{border-left:3px solid var(--msq-accent);padding:6px 14px;color:var(--msq-muted);font-size:.97em}\n.msq-box{background:var(--msq-tint);border:1px solid var(--msq-line);border-radius:12px;padding:0}\n.msq-box>summary{cursor:pointer;list-style:none;padding:14px 18px;font-weight:700;color:var(--msq-accent)}\n.msq-box>summary::-webkit-details-marker{display:none}\n.msq-box>summary::before{content:\"+\";display:inline-block;width:1.1em;font-weight:800}\n.msq-box[open]>summary::before{content:\"\\00d7\"}\n.msq-body{padding:2px 18px 18px}\n.msq-intro{margin:0 0 12px;font-size:.95em;color:var(--msq-muted)}\n.msq-list{margin:0;padding:0;list-style:none}\n.msq-q{margin:0 0 18px;padding:0}\n.msq-question{font-weight:700;margin:0 0 8px}\n.msq-options{display:flex;flex-direction:column;gap:8px}\n.msq-opt{text-align:left;background:var(--msq-base);border:1px solid var(--msq-line);border-radius:8px;padding:10px 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solid var(--msq-muted);border-radius:8px;font:inherit;background:#fff}\n.msq-btn{background:var(--msq-accent);color:var(--msq-accent-text);border:0;border-radius:8px;padding:11px 18px;font:inherit;font-weight:700;cursor:pointer}\n.msq-btn:hover{filter:brightness(.92)}\n.msq-btn[disabled]{opacity:.7;cursor:default}\n.msq-no{font-size:.9em;color:var(--msq-muted);margin-left:4px}\n.msq-privacy{margin:6px 0 0;font-size:.82em;color:var(--msq-muted);flex-basis:100%}\n.msq-hp{position:absolute;left:-5000px;width:1px;height:1px;overflow:hidden}\n.msq-msg{margin:8px 0 0;font-size:.92em}\n.msq-end{margin:1.5em 0;padding:18px;border:1px solid var(--msq-accent);border-radius:12px;text-align:center;background:var(--msq-tint)}\n.msq-end p{margin:0 0 12px}\n.msq-end .msq-body{text-align:left;padding:16px 0 0}\n.msq-end .msq-start-test[hidden]{display:none}\n.msq-tool{margin:1.5em 0;padding:18px 20px;background:var(--msq-tint);border:1px solid var(--msq-line);border-radius:12px}\n.msq-tool h3{margin:0 0 6px;font-size:1.15em}\n.msq-tool p{margin:0 0 10px}\n.msq-tool .msq-note{font-size:.85em;color:var(--msq-muted);margin:10px 0 0}\n.msq-check label{display:flex;gap:10px;align-items:flex-start;padding:9px 0;border-bottom:1px solid var(--msq-line);cursor:pointer;line-height:1.4}\n.msq-check label:last-of-type{border-bottom:0}\n.msq-check input{margin-top:5px;flex:0 0 auto;width:18px;height:18px;accent-color:var(--msq-accent)}\n.msq-check-count{font-weight:700;margin:10px 0 0}\n.msq-verdict-box{margin:12px 0 0;padding:10px 14px;border-radius:8px;background:var(--msq-base);border-left:3px solid var(--msq-warn)}\n.msq-verdict-box[hidden]{display:none}\n.msq-calc{display:grid;grid-template-columns:1fr 1fr;gap:10px 16px}\n.msq-calc label{display:flex;flex-direction:column;gap:4px;font-size:.92em}\n.msq-calc input,.msq-calc select{padding:8px 10px;border:1px solid var(--msq-muted);border-radius:8px;font:inherit;background:#fff}\n.msq-calc-out{grid-column:1 \/ -1;margin-top:6px;padding:12px 14px;background:var(--msq-base);border-radius:8px;border:1px solid var(--msq-line)}\n.msq-calc-out strong{font-size:1.15em}\n.msq-choose label{display:block;padding:9px 12px;margin:0 0 8px;background:var(--msq-base);border:1px solid var(--msq-line);border-radius:8px;cursor:pointer}\n.msq-choose input{margin-right:8px;accent-color:var(--msq-accent)}\n.msq-choice-result{margin-top:10px;padding:12px 14px;background:var(--msq-base);border-left:3px solid var(--msq-accent);border-radius:0 8px 8px 0}\n.msq-choice-result[hidden]{display:none}\n@media (max-width:600px){.msq-calc{grid-template-columns:1fr}}\nh2.wp-block-heading[id]{scroll-margin-top:24px}<\/style>\n<noscript><style>.msq-explain{display:block !important}<\/style><\/noscript>\n<details class=\"msq-box\">\n<summary>Think you already know this? Five questions, one minute.<\/summary>\n<div class=\"msq-body\">\n<p class=\"msq-intro\">Every answer is on this page. Answer from what you know now; the page fills in the rest.<\/p>\n<ol class=\"msq-list\">\n<li class=\"msq-q\" data-q=\"1\" data-answer=\"a\" data-title=\"When did fertilisation actually happen in an IVF cycle?\" data-section=\"#when-did-fertilisation-actually-happen-in-an-ivf-cycle\">\n<p class=\"msq-question\">1. When is fertilisation checked in an IVF cycle?<\/p>\n<div class=\"msq-options\" role=\"group\" aria-label=\"Question 1 options\"><button type=\"button\" class=\"msq-opt\" data-opt=\"a\">The morning after egg collection, under a microscope, by looking for two pronuclei<\/button><button type=\"button\" class=\"msq-opt\" data-opt=\"b\">On transfer day<\/button><button type=\"button\" class=\"msq-opt\" data-opt=\"c\">At the blood test<\/button><\/div>\n<p class=\"msq-explain\" hidden><span class=\"msq-verdict\"><\/span>Roughly sixteen to eighteen hours after the eggs and sperm are put together, in a dish, by an embryologist. <a href=\"https:\/\/www.hfea.gov.uk\/treatments\/explore-all-treatments\/in-vitro-fertilisation-ivf\/\" target=\"_blank\" rel=\"noopener\">The HFEA<\/a> describes embryos then developing for between two and six days before transfer. <a class=\"msq-section\" href=\"#when-did-fertilisation-actually-happen-in-an-ivf-cycle\">Read the section<\/a><\/p>\n<\/li>\n<li class=\"msq-q\" data-q=\"2\" data-answer=\"b\" data-title=\"Why do the general pregnancy articles not apply to you?\" data-section=\"#why-do-the-general-pregnancy-articles-not-apply-to-you\">\n<p class=\"msq-question\">2. In conception without treatment, when does the embryo first attach to the uterus, per the NICHD?<\/p>\n<div class=\"msq-options\" role=\"group\" aria-label=\"Question 2 options\"><button type=\"button\" class=\"msq-opt\" data-opt=\"a\">The same day as fertilisation<\/button><button type=\"button\" class=\"msq-opt\" data-opt=\"b\">Around five or six days after ovulation, firmer between six and twelve<\/button><button type=\"button\" class=\"msq-opt\" data-opt=\"c\">Three weeks later<\/button><\/div>\n<p class=\"msq-explain\" hidden><span class=\"msq-verdict\"><\/span><a href=\"https:\/\/www.nichd.nih.gov\/health\/topics\/menstruation\/conditioninfo\" target=\"_blank\" rel=\"noopener\">The NICHD<\/a> describes attachment around five or six days after ovulation. In IVF the week before that happened in a laboratory, which is why articles about feeling conception describe a different situation. <a class=\"msq-section\" href=\"#why-do-the-general-pregnancy-articles-not-apply-to-you\">Read the section<\/a><\/p>\n<\/li>\n<li class=\"msq-q\" data-q=\"3\" data-answer=\"b\" data-title=\"What does the clinic tell you at each step, and when?\" data-section=\"#what-does-the-clinic-tell-you-at-each-step-and-when\">\n<p class=\"msq-question\">3. In the Cambridge University Hospitals laboratory guide, roughly what share of injected eggs fertilise normally with ICSI?<\/p>\n<div class=\"msq-options\" role=\"group\" aria-label=\"Question 3 options\"><button type=\"button\" class=\"msq-opt\" data-opt=\"a\">About 10 to 20 percent<\/button><button type=\"button\" class=\"msq-opt\" data-opt=\"b\">About 60 to 70 percent<\/button><button type=\"button\" class=\"msq-opt\" data-opt=\"c\">Always 100 percent<\/button><\/div>\n<p class=\"msq-explain\" hidden><span class=\"msq-verdict\"><\/span><a href=\"https:\/\/web.archive.org\/web\/20251014044657\/https:\/\/www.cuh.nhs.uk\/patient-information\/laboratory-guide-for-patients\/\" target=\"_blank\" rel=\"noopener\">The guide<\/a> gives approximately sixty to seventy percent, with typically around half of embryos reaching the blastocyst stage by day five. Figures vary between laboratories, so the ones your own clinic quotes are the ones that describe your treatment. <a class=\"msq-section\" href=\"#what-does-the-clinic-tell-you-at-each-step-and-when\">Read the section<\/a><\/p>\n<\/li>\n<li class=\"msq-q\" data-q=\"4\" data-answer=\"a\" data-title=\"So what are you feeling after the transfer, if not fertilisation?\" data-section=\"#so-what-are-you-feeling-after-the-transfer-if-not-fertilisat\">\n<p class=\"msq-question\">4. Which of these is a documented cause of sensation in the fortnight after transfer?<\/p>\n<div class=\"msq-options\" role=\"group\" aria-label=\"Question 4 options\"><button type=\"button\" class=\"msq-opt\" data-opt=\"a\">Luteal phase medication, the transfer procedure and everyday gut changes<\/button><button type=\"button\" class=\"msq-opt\" data-opt=\"b\">The embryo signalling that it has implanted<\/button><button type=\"button\" class=\"msq-opt\" data-opt=\"c\">Nothing; sensations in this fortnight are imagined<\/button><\/div>\n<p class=\"msq-explain\" hidden><span class=\"msq-verdict\"><\/span>The documented causes are ordinary: the medication, the procedure and the full bladder it needs, the after effects of stimulation in a fresh cycle, and gut changes. Implantation is on the list and is the one item nobody can point to, and feeling nothing is not information either. <a class=\"msq-section\" href=\"#so-what-are-you-feeling-after-the-transfer-if-not-fertilisat\">Read the section<\/a><\/p>\n<\/li>\n<li class=\"msq-q\" data-q=\"5\" data-answer=\"a\" data-title=\"What can you actually know before the blood test?\" data-section=\"#what-can-you-actually-know-before-the-blood-test\">\n<p class=\"msq-question\">5. What can you know for certain before the blood test?<\/p>\n<div class=\"msq-options\" role=\"group\" aria-label=\"Question 5 options\"><button type=\"button\" class=\"msq-opt\" data-opt=\"a\">The laboratory facts: dates, the numbers from each call, what was transferred and when you test<\/button><button type=\"button\" class=\"msq-opt\" data-opt=\"b\">Whether implantation happened, from cramps<\/button><button type=\"button\" class=\"msq-opt\" data-opt=\"c\">Nothing at all<\/button><\/div>\n<p class=\"msq-explain\" hidden><span class=\"msq-verdict\"><\/span>The laboratory facts are the complete set until the blood test is taken. The test measures hCG, the hormone released as implantation progresses, which is why its timing matters more than most people realise. <a class=\"msq-section\" href=\"#what-can-you-actually-know-before-the-blood-test\">Read the section<\/a><\/p>\n<\/li>\n<\/ol>\n<div class=\"msq-result\" hidden><\/div>\n<\/div>\n<\/details>\n<script>(function(){\n  if (window.__msqInit) { return; }\n  window.__msqInit = true;\n  var root = document.getElementById('ms-quiz');\n  if (!root) { return; }\n  var meta = { slug: root.getAttribute('data-slug'), category: root.getAttribute('data-category'),\n               list: root.getAttribute('data-list') || '1' };\n  function qs(el, s){ return el.querySelector(s); }\n  function qsa(el, s){ return Array.prototype.slice.call(el.querySelectorAll(s)); }\n  function track(name, params){\n    try { if (typeof gtag === 'function') { var p = params || {}; p.article = meta.slug; gtag('event', name, p); } } catch (e) {}\n  }\n  function jumpList(missed){\n    if (!missed.length) { return ''; }\n    return '<ul class=\"msq-jump\">' + missed.map(function(q){\n      return '<li><a href=\"' + q.getAttribute('data-section') + '\">' + q.getAttribute('data-title') + '<\/a><\/li>';\n    }).join('') + '<\/ul>';\n  }\n  function emailForm(){\n    return '<div class=\"msq-sub\"><p><strong>Get the next one.<\/strong> We publish new articles on ' + meta.category\n      + ' most weeks and recheck this page on Sundays. 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A delegated listener finds it at click time. *\/\n  document.addEventListener('click', function(e){\n    var startBtn = (e.target && e.target.closest) ? e.target.closest('.msq-start-test') : null;\n    if (!startBtn) { return; }\n    var end = startBtn.closest('.msq-end');\n    if (!end) { return; }\n    var mount = qs(end, '.msq-mount');\n    var clone = qs(root, '.msq-body').cloneNode(true);\n    var intro = qs(clone, '.msq-intro');\n    if (intro) { intro.textContent = 'The same five questions, now that you have read the page.'; }\n    var res = qs(clone, '.msq-result'); if (res) { res.hidden = true; res.innerHTML = ''; }\n    mount.innerHTML = ''; mount.appendChild(clone);\n    setup(mount, 'test');\n    startBtn.hidden = true;\n    track('quiz_open', { mode: 'test' });\n    mount.scrollIntoView({ behavior: 'smooth', block: 'start' });\n    var first = qs(mount, '.msq-opt'); if (first) { first.focus({ preventScroll: true }); }\n  });\n  \/* Shared tool behaviour: checklists remember their ticks on this device, and a chooser\n     shows the result for the option picked. Calculators carry their own small script. *\/\n  function initTools(){\n    qsa(document, '.msq-check').forEach(function(box){\n      var key = 'msq-check-' + meta.slug + '-' + (box.getAttribute('data-id') || 'x');\n      var boxes = qsa(box, 'input[type=checkbox]'), count = qs(box, '.msq-check-count');\n      var yes = qs(box, '.msq-verdict-yes'), no = qs(box, '.msq-verdict-no');\n      var saved = {};\n      try { saved = JSON.parse(localStorage.getItem(key) || '{}'); } catch (e) {}\n      boxes.forEach(function(cb, i){ if (saved[i]) { cb.checked = true; } });\n      function refresh(){\n        var n = boxes.filter(function(cb){ return cb.checked; }).length, state = {};\n        boxes.forEach(function(cb, i){ if (cb.checked) { state[i] = 1; } });\n        try { localStorage.setItem(key, JSON.stringify(state)); } catch (e) {}\n        if (count) { count.textContent = n + ' of ' + boxes.length + (box.getAttribute('data-verb') || ' done'); }\n        if (yes && no) { yes.hidden = n === 0; no.hidden = n !== 0; }\n      }\n      boxes.forEach(function(cb){ cb.addEventListener('change', function(){ refresh(); track('tool_check', { tool: box.getAttribute('data-id') }); }); });\n      refresh();\n    });\n    qsa(document, '.msq-choose').forEach(function(box){\n      var results = qsa(box, '.msq-choice-result');\n      qsa(box, 'input[type=radio]').forEach(function(r){\n        r.addEventListener('change', function(){\n          results.forEach(function(el){ el.hidden = el.getAttribute('data-for') !== r.value; });\n          track('tool_choose', { tool: box.getAttribute('data-id'), choice: r.value });\n        });\n      });\n    });\n  }\n  \/\/ read progress: how far down the article the reader has scrolled, fired once per quarter\n  (function(){\n    var art = root.closest('article') || root.parentNode, fired = {};\n    function check(){\n      var top = art.getBoundingClientRect().top + window.pageYOffset, h = art.offsetHeight || 1;\n      var seen = (window.pageYOffset + window.innerHeight - top) \/ h * 100;\n      [25, 50, 75, 100].forEach(function(m){ if (seen >= m && !fired[m]) { fired[m] = true; track('read_progress', { percent: m }); } });\n    }\n    window.addEventListener('scroll', check, { passive: true }); window.addEventListener('load', check);\n  })();\n  if (document.readyState === 'loading') { document.addEventListener('DOMContentLoaded', initTools); } else { initTools(); }\n})();<\/script>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">This is the one search term where the ordinary pregnancy internet is not just unhelpful but answering a different question. Articles about signs of conception describe something happening inside a fallopian tube. In IVF that step happened in an incubator, and reached you as a number over the phone.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">That does not make the question silly. It makes it worth answering properly, because once the timeline is clear a lot of what you are trying to interpret stops being interpretable, which is oddly a relief at three in the morning.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"when-did-fertilisation-actually-happen-in-an-ivf-cycle\">When did fertilisation actually happen in an IVF cycle?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">On the day of your egg collection, or the following morning at the latest. The eggs are collected and taken to the laboratory the same day, and the sperm is either mixed with them or injected into them within hours. The <a href=\"https:\/\/www.hfea.gov.uk\/treatments\/explore-all-treatments\/in-vitro-fertilisation-ivf\/\" rel=\"nofollow noopener\" target=\"_blank\">Human Fertilisation and Embryology Authority<\/a> describes the step simply: the eggs are mixed with the sperm in a laboratory, with the aim that they fertilise to create an embryo.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Whether fertilisation worked is checked the next morning, roughly sixteen to eighteen hours after the eggs and sperm were put together, by looking down a microscope for two pronuclei in each egg. Two pronuclei means one set of genetic material from each side, which is what normal fertilisation looks like at that moment. It is a visual check on a dish, and none of it happens inside you.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">From there the embryos are grown on. The HFEA states that if fertilisation is successful the embryos are allowed to develop for between two and six days, and that the transfer takes place two to five days after fertilisation. So by transfer day, fertilisation is already old news.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1200\" height=\"627\" src=\"https:\/\/ivfprep.guide\/articles\/wp-content\/uploads\/2026\/09\/signs-of-fertilization-2.jpg\" alt=\"Embryologist at a microscope in a laboratory, where fertilization happens in an IVF cycle\" class=\"wp-image-80\" srcset=\"https:\/\/ivfprep.guide\/articles\/wp-content\/uploads\/2026\/09\/signs-of-fertilization-2.jpg 1200w, https:\/\/ivfprep.guide\/articles\/wp-content\/uploads\/2026\/09\/signs-of-fertilization-2-300x157.jpg 300w, https:\/\/ivfprep.guide\/articles\/wp-content\/uploads\/2026\/09\/signs-of-fertilization-2-1024x535.jpg 1024w, https:\/\/ivfprep.guide\/articles\/wp-content\/uploads\/2026\/09\/signs-of-fertilization-2-768x401.jpg 768w\" sizes=\"auto, (max-width: 1200px) 100vw, 1200px\" \/><figcaption class=\"wp-block-image__caption\">Fertilisation is confirmed under a microscope, in a building, not inside you.<\/figcaption><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"why-do-the-general-pregnancy-articles-not-apply-to-you\">Why do the general pregnancy articles not apply to you?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Because they are describing a first week that, in your cycle, took place outside your body. In conception without treatment, <a href=\"https:\/\/www.nichd.nih.gov\/health\/topics\/menstruation\/conditioninfo\" rel=\"nofollow noopener\" target=\"_blank\">the Eunice Kennedy Shriver National Institute of Child Health and Human Development<\/a> describes the embryo first attaching to the wall of the uterus around five or six days after ovulation, and becoming more firmly implanted between six and twelve days after ovulation. Everything before that attachment is happening in a tube nobody can feel.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">An IVF cycle splits that week in half and puts a laboratory in the middle of it. The half people write blog posts about is the half you were watched through a microscope for.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><thead><tr><th>Stage<\/th><th>Conceiving without treatment<\/th><th>In an IVF cycle<\/th><\/tr><\/thead><tbody><tr><td>Fertilisation<\/td><td>Happens in the fallopian tube, unobserved, at an unknown hour.<\/td><td>Happens in a dish in the laboratory, on a recorded day, and is checked the next morning.<\/td><\/tr><tr><td>The first few days of the embryo<\/td><td>The embryo travels down the tube while you carry on with your week.<\/td><td>The embryo is in an incubator and is graded on set days.<\/td><\/tr><tr><td>How you find out anything<\/td><td>You do not, until a test is late enough to be positive.<\/td><td>The laboratory telephones you with numbers at each stage.<\/td><\/tr><tr><td>What there is to feel<\/td><td>Nothing has been shown to be felt at any of these steps.<\/td><td>Nothing, because these steps are not happening in your body at all.<\/td><\/tr><tr><td>Implantation<\/td><td>Around five or six days after ovulation, firmer between six and twelve.<\/td><td>Begins after the transfer, over a period rather than at a moment.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">It is why searching for the feeling of fertilisation returns pages that do not quite fit. They were written for a different situation.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"what-does-the-clinic-tell-you-at-each-step-and-when\">What does the clinic tell you at each step, and when?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">More than most people expect, and on a fairly fixed schedule. Laboratories publish this. The <a href=\"https:\/\/web.archive.org\/web\/20251014044657\/https:\/\/www.cuh.nhs.uk\/patient-information\/laboratory-guide-for-patients\/\" rel=\"nofollow noopener\" target=\"_blank\">laboratory guide for patients at Cambridge University Hospitals<\/a> sets out the calls: the team confirms the number of eggs collected and the insemination method on the day, telephones on the morning of the fertilisation check, usually before half past ten, and calls again between eight and ten on day five to confirm the plan for transfer.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Other clinics run different hours and call points, and yours may grade on day three rather than day five. The shape holds even when the details differ. Your clinic tells you what happened in the laboratory. You are not expected to deduce it.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><thead><tr><th>Point in the cycle<\/th><th>What the laboratory is doing<\/th><th>What you are usually told<\/th><th>Anything to feel?<\/th><\/tr><\/thead><tbody><tr><td>Egg collection day<\/td><td>Eggs identified, sperm prepared, insemination or injection carried out.<\/td><td>How many eggs were collected and which method was used.<\/td><td>Soreness from the procedure and sedation. Nothing from fertilisation.<\/td><\/tr><tr><td>The next morning<\/td><td>Checking each egg under a microscope for two pronuclei.<\/td><td>How many fertilised normally, by phone.<\/td><td>No. This is happening in a dish.<\/td><\/tr><tr><td>Days two and three<\/td><td>Embryos dividing into a handful of cells, graded on set days.<\/td><td>Often a brief update, depending on the clinic.<\/td><td>No.<\/td><\/tr><tr><td>Day five<\/td><td>Seeing which embryos have reached the blastocyst stage.<\/td><td>The plan for transfer or freezing, by phone.<\/td><td>No.<\/td><\/tr><tr><td>Transfer day<\/td><td>The chosen embryo is loaded and placed with a soft catheter.<\/td><td>What was transferred and the date of your blood test.<\/td><td>The procedure itself, which is usually mild.<\/td><\/tr><tr><td>The fortnight after<\/td><td>Nothing. The laboratory work is finished.<\/td><td>Nothing until the blood test.<\/td><td>Plenty, and none of it readable.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Two numbers from that Cambridge guide are worth holding onto, because they set expectations that nobody sets for you in advance. Approximately sixty to seventy percent of injected eggs fertilise normally with intracytoplasmic sperm injection, and typically around half of embryos have started developing into blastocysts by day five. Figures vary between laboratories and between individual cycles, so the ones your own clinic quotes are the ones that describe your treatment. If the day five call is the one you are waiting on, <a href=\"https:\/\/ivfprep.guide\/articles\/good-quality-5-day-embryo-blastocyst\/\">what a blastocyst grade actually means, letter by letter<\/a> explains the vocabulary they will use on it.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1200\" height=\"627\" src=\"https:\/\/ivfprep.guide\/articles\/wp-content\/uploads\/2026\/09\/signs-of-fertilization-3.jpg\" alt=\"Woman on a sofa holding a phone, waiting for the clinic call about fertilization results\" class=\"wp-image-81\" srcset=\"https:\/\/ivfprep.guide\/articles\/wp-content\/uploads\/2026\/09\/signs-of-fertilization-3.jpg 1200w, https:\/\/ivfprep.guide\/articles\/wp-content\/uploads\/2026\/09\/signs-of-fertilization-3-300x157.jpg 300w, https:\/\/ivfprep.guide\/articles\/wp-content\/uploads\/2026\/09\/signs-of-fertilization-3-1024x535.jpg 1024w, https:\/\/ivfprep.guide\/articles\/wp-content\/uploads\/2026\/09\/signs-of-fertilization-3-768x401.jpg 768w\" sizes=\"auto, (max-width: 1200px) 100vw, 1200px\" \/><figcaption class=\"wp-block-image__caption\">Most clinics telephone the fertilisation result on a set morning, not on request.<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1600\" height=\"900\" src=\"https:\/\/ivfprep.guide\/articles\/wp-content\/uploads\/2026\/09\/signs-of-fertilization-chart.png\" alt=\"Timeline of when the laboratory calls, the real signs of fertilization: collection, next morning check, day five, transfer.\" class=\"wp-image-235\" srcset=\"https:\/\/ivfprep.guide\/articles\/wp-content\/uploads\/2026\/09\/signs-of-fertilization-chart.png 1600w, https:\/\/ivfprep.guide\/articles\/wp-content\/uploads\/2026\/09\/signs-of-fertilization-chart-300x169.png 300w, https:\/\/ivfprep.guide\/articles\/wp-content\/uploads\/2026\/09\/signs-of-fertilization-chart-1024x576.png 1024w, https:\/\/ivfprep.guide\/articles\/wp-content\/uploads\/2026\/09\/signs-of-fertilization-chart-768x432.png 768w, https:\/\/ivfprep.guide\/articles\/wp-content\/uploads\/2026\/09\/signs-of-fertilization-chart-1536x864.png 1536w\" sizes=\"auto, (max-width: 1600px) 100vw, 1600px\" \/><figcaption class=\"wp-block-image__caption\">The call points from the Cambridge University Hospitals laboratory guide. Other clinics run different hours and may grade on day three, but the shape holds: the clinic tells you what happened, you are not expected to deduce it.<\/figcaption><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"so-what-are-you-feeling-after-the-transfer-if-not-fertilisat\">So what are you feeling after the transfer, if not fertilisation?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Something real, almost certainly, and something that cannot be traced back to an outcome. The documented causes of sensation in this fortnight are ordinary and well described: the medication used to support the luteal phase, the transfer procedure and the full bladder it needs, the after effects of stimulation in a fresh cycle, and the everyday gut changes that come with all of it. None of them separate cleanly from each other while they are happening. The luteal support is the loudest of the four, and its label reads almost exactly like a period about to start, which is why <a href=\"https:\/\/ivfprep.guide\/articles\/day-9-after-transfer-period-feeling\/\">the premenstrual feeling that arrives around day 9 has a pharmacological explanation<\/a> rather than a predictive one.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Implantation is on that list too, and it is the one item nobody can point to. No method exists for distinguishing a sensation caused by implantation from a sensation caused by any of the rest. That is not caution on our part. It is the state of the evidence, and it is why <a href=\"https:\/\/ivfprep.guide\/articles\/implantation-cramp-location\/\">the cramp maps you find on forums fall apart when you push on them<\/a>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">It also means the reverse. Feeling nothing at all is not information either, and the people who felt nothing are the least likely to have written about it, which is <a href=\"https:\/\/ivfprep.guide\/articles\/successful-implantation-without-bleeding\/\">the quietest and most useful fact on this site<\/a>. Nothing here is a reading of your own symptoms, because a website cannot do that honestly, and this one will not pretend otherwise.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"why-does-the-phrase-signs-of-fertilisation-exist-at-all\">Why does the phrase signs of fertilisation exist at all?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Partly because the words conception, fertilisation and implantation get used interchangeably in everyday speech, so a search for one returns content about another. Partly because the pregnancy content industry is enormous and was not built with IVF patients in mind. And partly because the fortnight after a transfer is unbearable in a very specific way, and people search the words that match the feeling rather than the biology.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The forum archives amplify it. A vivid post about a twinge on day three that ended in a positive result gets saved and quoted for years. The identical twinge that ended in a negative gets read as bad luck rather than as evidence against the pattern. The far larger group who noticed nothing worth mentioning and went back to work never post at all. What you are reading at two in the morning is a record of what was memorable, not a record of what happens, and every symptom list built from it inherits that bias. We go through the same problem in detail in <a href=\"https:\/\/ivfprep.guide\/articles\/signs-of-implantation\/\">our piece on what the signs of implantation actually show<\/a>.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"what-can-you-actually-know-before-the-blood-test\">What can you actually know before the blood test?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The laboratory facts, which you already have, and nothing else. The dates, the numbers from each call, what was transferred and when your clinic wants to test you. That is the complete set until the blood test is taken.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The test itself measures human chorionic gonadotrophin, the hormone released as implantation progresses, which is why timing it matters more than most people realise. We cover what the number means in <a href=\"https:\/\/ivfprep.guide\/articles\/beta-hcg-test-explained\/\">the article on beta hCG<\/a>, and why testing at home earlier than the clinic advises can mislead you after IVF in <a href=\"https:\/\/ivfprep.guide\/articles\/home-pregnancy-test-after-ivf\/\">the piece on trigger shots and home tests<\/a>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If any part of your own timeline is unclear, the people who can answer it are the ones holding your notes. Your clinic knows your protocol, what was transferred, which day it was grown to and when your test is booked. This site knows none of those things, and no article can. Ask them. They have been asked this exact question before, and nobody there will find it a strange thing to want to know.<\/p>\n\n\n\n<div class=\"msq-tool\" id=\"clinic-calls\">\n<h3>What the laboratory told you, call by call<\/h3>\n<p>The laboratory facts are the complete set of what can be known before the blood test. Keep each call here so nothing has to be reconstructed at two in the morning.<\/p>\n<div class=\"msq-calc\">\n<label>Date<input type=\"date\" name=\"date\"><\/label>\n<label>Which call<select name=\"call\"><option value=\"\">Choose<\/option><option>Egg collection day<\/option><option>Fertilisation check, next morning<\/option><option>Day two or three update<\/option><option>Day five plan<\/option><option>Transfer day<\/option><option>Test date given<\/option><\/select><\/label>\n<label>What they said<input type=\"text\" name=\"said\" maxlength=\"120\" placeholder=\"numbers, method, plan, dates\"><\/label>\n\n<div class=\"msq-calc-out\"><button type=\"button\" class=\"msq-btn\" id=\"clinic-calls-add\">Add this entry<\/button> <a href=\"#\" class=\"msq-no\" id=\"clinic-calls-clear\">Clear all<\/a>\n<div id=\"clinic-calls-list\" style=\"margin-top:10px;overflow-x:auto\"><\/div><\/div>\n<\/div>\n<p class=\"msq-note\">Kept on this device only. Your clinic holds your notes; this is the copy for your own pocket.<\/p>\n<\/div>\n<script>\n(function(){\n  var root = document.getElementById('clinic-calls'); if (!root) { return; }\n  var names = ['date','call','said'], key = 'msq-log-signs-of-fertilization-clinic-calls';\n  var ins = names.map(function(n){ return root.querySelector('[name=\"' + n + '\"]'); });\n  var list = document.getElementById('clinic-calls-list');\n  function load(){ try { return JSON.parse(localStorage.getItem(key) || '[]'); } catch (e) { return []; } }\n  function save(rows){ try { localStorage.setItem(key, JSON.stringify(rows)); } catch (e) {} }\n  function esc(s){ return String(s).replace(\/&\/g, '&amp;').replace(\/<\/g, '&lt;').replace(\/>\/g, '&gt;'); }\n  function render(){\n    var rows = load();\n    if (!rows.length) { list.innerHTML = '<p class=\"msq-note\">Nothing logged yet.<\/p>'; return; }\n    var h = '<table><thead><tr><th>Date<\/th><th>Which call<\/th><th>What they said<\/th><\/tr><\/thead><tbody>';\n    rows.slice(0, 30).forEach(function(r){ h += '<tr>' + names.map(function(n){ return '<td>' + esc(r[n] || '') + '<\/td>'; }).join('') + '<\/tr>'; });\n    list.innerHTML = h + '<\/tbody><\/table><p class=\"msq-note\">' + rows.length + ' entries, newest first.<\/p>';\n  }\n  document.getElementById('clinic-calls-add').addEventListener('click', function(){\n    var r = {}; var any = false;\n    ins.forEach(function(el, i){ r[names[i]] = el ? el.value : ''; if (el && el.value) { any = true; } });\n    if (!any) { return; }\n    var rows = load(); rows.unshift(r); save(rows); render();\n    ins.forEach(function(el){ if (el && el.type !== 'date') { el.value = ''; } });\n    try { if (typeof gtag === 'function') { gtag('event', 'tool_log', { tool: 'clinic-calls', article: 'signs-of-fertilization' }); } } catch (e) {}\n  });\n  document.getElementById('clinic-calls-clear').addEventListener('click', function(e){ e.preventDefault(); save([]); render(); });\n  render();\n})();\n<\/script>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"what-has-changed-since-this-was-first-published\">What has changed since this was first published?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Nothing in the timeline above, and on this subject that is the useful answer rather than a dull one. Everything here was rechecked on 20 September 2026 against the same two documents it was written from.<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li><strong>The HFEA page still says what it said.<\/strong> Embryos developed for between two and six days, transfer two to five days after fertilisation, rechecked on the <a href=\"https:\/\/www.hfea.gov.uk\/treatments\/explore-all-treatments\/in-vitro-fertilisation-ivf\/\" rel=\"nofollow noopener\" target=\"_blank\">HFEA treatment page<\/a> itself. One detail worth knowing, given how much of the internet paraphrases that page: it carries a publication date of 9 March 2016.<\/li><li><strong>The Cambridge laboratory figures are unchanged, word for word.<\/strong> Approximately 60 to 70 percent of injected eggs fertilising normally with ICSI, typically around 50 percent of embryos reaching blastocyst by day five, the fertilisation check call usually before half past ten and the day five call between eight and ten. The <a href=\"https:\/\/web.archive.org\/web\/20251014044657\/https:\/\/www.cuh.nhs.uk\/patient-information\/laboratory-guide-for-patients\/\" rel=\"nofollow noopener\" target=\"_blank\">guide<\/a> is at version 2, approved 25 November 2021.<\/li><li><strong>Which is rather the point of the page.<\/strong> The two published documents behind it have not been revised in years, while the numbers your own clinic quotes are its own and do move. Where your clinic&#8217;s figures differ from the ones above, your clinic&#8217;s are the ones describing your treatment.<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"frequently-asked-questions\">Frequently asked questions<\/h2>\n\n\n<div id=\"rank-math-faq\" class=\"rank-math-block\">\n<div class=\"rank-math-list \">\n<div id=\"faq-q-1\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">Can you feel fertilisation after an embryo transfer?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>No. In IVF, fertilisation takes place in a laboratory dish on or just after the day of egg collection, days before the transfer. It is confirmed by an embryologist looking down a microscope for two pronuclei, and the result is telephoned to you. Nothing about that step happens inside your body, so there is nothing there to feel.<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-q-2\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">When exactly does fertilisation happen in an IVF cycle?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>Within hours of egg collection, when the eggs are mixed with sperm or injected. The check for normal fertilisation is done the following morning, roughly sixteen to eighteen hours later. The Human Fertilisation and Embryology Authority says embryos are then grown for between two and six days, with transfer two to five days after fertilisation.<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-q-3\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">How many eggs usually fertilise?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>It varies by laboratory and by cycle. The laboratory guide published by Cambridge University Hospitals gives approximately sixty to seventy percent of injected eggs fertilising normally with intracytoplasmic sperm injection, and typically around half of embryos reaching the blastocyst stage by day five. Your own clinic&#8217;s figures are the ones that describe your treatment.<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-q-4\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">Is implantation different from fertilisation?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>Yes, and in IVF they are separated by days and by location. Fertilisation happens in the laboratory before transfer. Implantation begins after the embryo is placed in the uterus and unfolds over a period rather than at a single moment. Neither has been shown to produce a sensation you could identify at the time.<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-q-5\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">What are the twinges after a transfer, then?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>Usually something ordinary and untraceable. Luteal phase medication, the transfer procedure itself, the after effects of stimulation in a fresh cycle and everyday gut changes all produce sensations in this fortnight. No method exists for telling any of them apart from implantation while it is happening, in either direction.<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-q-6\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">Should I be worried if I feel nothing at all?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>Feeling nothing is not evidence about the outcome, in either direction. People who notice nothing are the group least likely to post about it, so forums systematically underrepresent them and make silence look rarer than it is. Any symptom or its absence still has to wait for the blood test your clinic has booked.<\/p>\n\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n<div class=\"msq-end\" id=\"ms-quiz-end\">\n<p><strong>Finished the page?<\/strong> The same five questions from the top, to see what stuck.<\/p>\n<button type=\"button\" class=\"msq-btn msq-start-test\">Test Your Understanding of This Article<\/button>\n<div class=\"msq-mount\"><\/div>\n<\/div>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p class=\"wp-block-paragraph\"><em>This article is general information, not medical advice, and is not a substitute for care from a qualified healthcare professional. Speak to your doctor about your own situation.<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"<p>The search assumes fertilisation happens inside you. In an IVF cycle it happened in a dish, days earlier, and was phoned through as a number. Here is the actual timeline.<\/p>\n","protected":false},"author":1,"featured_media":79,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","rank_math_title":"Signs of Fertilization After IVF Transfer: The Timeline Nobody Explains","rank_math_description":"In IVF, fertilisation happens in the lab days before transfer, so there is nothing to feel. The real timeline, and what your clinic tells you at each step.","rank_math_focus_keyword":"signs of fertilization","rank_math_canonical_url":"","rank_math_breadcrumb_title":"","rank_math_facebook_title":"","rank_math_facebook_description":"","rank_math_facebook_image":"","rank_math_twitter_title":"","rank_math_twitter_description":"","rank_math_twitter_image":"","rank_math_pillar_content":"","rank_math_robots":[],"rank_math_advanced_robots":[]},"categories":[5],"tags":[],"class_list":["post-82","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-understanding-ivf"],"_links":{"self":[{"href":"https:\/\/ivfprep.guide\/articles\/wp-json\/wp\/v2\/posts\/82","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ivfprep.guide\/articles\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ivfprep.guide\/articles\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ivfprep.guide\/articles\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ivfprep.guide\/articles\/wp-json\/wp\/v2\/comments?post=82"}],"version-history":[{"count":8,"href":"https:\/\/ivfprep.guide\/articles\/wp-json\/wp\/v2\/posts\/82\/revisions"}],"predecessor-version":[{"id":343,"href":"https:\/\/ivfprep.guide\/articles\/wp-json\/wp\/v2\/posts\/82\/revisions\/343"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/ivfprep.guide\/articles\/wp-json\/wp\/v2\/media\/79"}],"wp:attachment":[{"href":"https:\/\/ivfprep.guide\/articles\/wp-json\/wp\/v2\/media?parent=82"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ivfprep.guide\/articles\/wp-json\/wp\/v2\/categories?post=82"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ivfprep.guide\/articles\/wp-json\/wp\/v2\/tags?post=82"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}