{"id":32768,"date":"2021-02-08T18:34:29","date_gmt":"2021-02-08T16:34:29","guid":{"rendered":"https:\/\/www.juanacrespo.es\/?p=32768"},"modified":"2021-02-08T18:34:29","modified_gmt":"2021-02-08T16:34:29","slug":"embrio-implantation-process","status":"publish","type":"post","link":"https:\/\/www.old.juanacrespo.es\/en\/embrio-implantation-process\/","title":{"rendered":"How is the embryo implantation process?"},"content":{"rendered":"<p>The<strong> embryonic implantation<\/strong> is the process by which the embryo, already transferred into the mother&#8217;s uterus, attaches to the endometrium and penetrates into its interior to continue developing.<\/p>\n<p>Also known as &#8220;nidation&#8221;, the implantation of the embryo usually takes place <strong>between 5 and 6 days after the egg is fertilized<\/strong>. Fertilization can be performed using two possible techniques:<\/p>\n<ul>\n<li><strong>Conventional IVF<\/strong><\/li>\n<\/ul>\n<p>In the IVF laboratory, we will put the egg in contact with an already treated semen sample so that one of the sperm fertilizes the egg in a spontaneous and natural way.<\/p>\n<ul>\n<li><strong>ICSI or <a href=\"https:\/\/embryo.asu.edu\/pages\/intracytoplasmic-sperm-injection\" target=\"_blank\" rel=\"noopener noreferrer\">Intracytoplasmic Sperm Injection<\/a> Technique<\/strong><\/li>\n<\/ul>\n<p>Also carried out in our laboratory, after the selection of the &#8220;optimal&#8221; sperm, we will perforate the cortex of the egg and deposit the male gamete directly into the cytoplasm.<\/p>\n<h2><span style=\"color: #b08f6e;\">Embryo implantation in IVF treatments<\/span><\/h2>\n<p>Embryo implantation is one of the most important and delicate phases of assisted reproduction treatments such as <a href=\"https:\/\/www.juanacrespo.es\/en\/treatment\/in-vitro-fertilisation\/\" target=\"_blank\" rel=\"noopener noreferrer\">In-Vitro Fertilization<\/a>, <a href=\"https:\/\/www.juanacrespo.es\/en\/treatment\/egg-donation\/\" target=\"_blank\" rel=\"noopener noreferrer\">egg donation<\/a> or embryo adoption.<\/p>\n<p>Its success depends on many aspects, the three most important being:<\/p>\n<ul>\n<li>The quality of the embryo.<\/li>\n<li>The receptivity of the uterus.<\/li>\n<li>The correct synchronization and interaction between both.<\/li>\n<\/ul>\n<p>This last one is much more important than it seems and, therefore, the objective will always be to <strong>transfer high-quality embryos at the right time<\/strong>. Otherwise, the success of the implantation may be compromised, since the dialogue between the uterus and the embryo would not be adequate.<\/p>\n<p>This is why our medical team carries out an exhaustive follow-up of the patient throughout the treatment, but especially during the endometrial preparation, scheduling the transfer at the time we consider most suitable for the mother-to-be.<\/p>\n<p><strong>The question is<\/strong>: when should the transfer be performed to ensure embryo implantation and what conditions should be present to make the uterus more receptive?<\/p>\n<p>Implantation occurs when the embryo has reached<strong> the blastocyst stage<\/strong>. At that moment (5-6 days after fertilization), it has about 200-400 cells and is made up of two differentiated parts:<\/p>\n<ul>\n<li>The inner cell mass (which will give rise to the embryo).<\/li>\n<li>The Trophectoderm (external cells that will form the placenta and other embryonic attachments).<\/li>\n<\/ul>\n<p>For implantation to take place, <strong>the endometrium must be perfectly prepared<\/strong> for implantation (with an endometrial thickness between 7-10 mm. and trilaminar aspect) and the molecules responsible for mediating the dialogue with the embryo (cytokines, integrins, adhesion molecules or growth factors, among others) must be expressed in the uterus.<\/p>\n<p>The days of greatest endometrial receptivity are known as the \u201c<strong>the implantation window<\/strong>&#8221; and include <strong>days 20-24 of the menstrual cycle <\/strong>in women with regular menstrual periods.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-29353 size-medium\" title=\"embryo implantation process\" src=\"https:\/\/www.juanacrespo.es\/wp-content\/uploads\/2020\/10\/mitad-de-texto-500x333.jpg\" alt=\"embryo implantation\" width=\"500\" height=\"333\" srcset=\"https:\/\/www.old.juanacrespo.es\/wp-content\/uploads\/2020\/10\/mitad-de-texto-200x133.jpg 200w, https:\/\/www.old.juanacrespo.es\/wp-content\/uploads\/2020\/10\/mitad-de-texto-400x267.jpg 400w, https:\/\/www.old.juanacrespo.es\/wp-content\/uploads\/2020\/10\/mitad-de-texto-500x333.jpg 500w, https:\/\/www.old.juanacrespo.es\/wp-content\/uploads\/2020\/10\/mitad-de-texto-600x400.jpg 600w, https:\/\/www.old.juanacrespo.es\/wp-content\/uploads\/2020\/10\/mitad-de-texto-768x512.jpg 768w, https:\/\/www.old.juanacrespo.es\/wp-content\/uploads\/2020\/10\/mitad-de-texto-800x533.jpg 800w, https:\/\/www.old.juanacrespo.es\/wp-content\/uploads\/2020\/10\/mitad-de-texto-1024x683.jpg 1024w, https:\/\/www.old.juanacrespo.es\/wp-content\/uploads\/2020\/10\/mitad-de-texto.jpg 1170w\" sizes=\"(max-width: 500px) 100vw, 500px\" \/><\/p>\n<h2><span style=\"color: #b08f6e;\">How long does it take and what are the stages of embryo implantation?<\/span><\/h2>\n<p><strong>Embryo implantation lasts 4-5 days<\/strong>, from the time the blastocyst hatches until the embryo completely invades the endometrium to adhere to it. This occurs between days 5 and 10 of its development, in a process that consists of several phases:<\/p>\n<ul>\n<li>Hatching<\/li>\n<\/ul>\n<p>Around days 5 and 6 of its development, the embryo &#8220;hatches&#8221; <strong>to shed its zona pellucida (or pellucid zone)<\/strong>, an outer layer that protects it. When the embryo manages to emerge from the zona pellucida, it begins to interact with the endometrium.<\/p>\n<ul>\n<li>Opposition<\/li>\n<\/ul>\n<p>Around the seventh day after fertilization, the embryo positions itself on the endometrial tissue.<\/p>\n<p>Thanks to pinopods, a type of morphological markers that only appear during the window of implantation, the inner cell mass orients itself towards the endometrium <strong>to ensure the placenta\u2019s development<\/strong>.<\/p>\n<ul>\n<li>Invasion and adhesion<\/li>\n<\/ul>\n<p>Once the embryo has found its natural position, it displaces the epithelial cells and invades the endometrial stroma, <strong>coming into contact with the maternal blood<\/strong>.<\/p>\n<p>At this moment, a &#8220;tear&#8221; is produced in the endometrium by which <strong>new endings are formed <\/strong>which amalgamate and allow the future embryo to adhere to the wall of the uterus for further development.<\/p>\n<h2><span style=\"color: #b08f6e;\">What are the signs that implantation has occurred?<\/span><\/h2>\n<p>Once the embryo has implanted, your body will begin to synthesize the beta-hCG hormone and, due to its effect, you may begin to experience some of <strong>the first symptoms of pregnancy<\/strong> (drowsiness or swelling, for example).<\/p>\n<p>Some women also notice slight <strong>discomfort similar to menstruation<\/strong>, although without significant pain.<\/p>\n<p>On the other hand, slight vaginal bleeding may occur. It is estimated that between 25 and 30% of women suffer from this small hemorrhage, known as &#8220;<a href=\"https:\/\/www.juanacrespo.es\/en\/how-to-recognize-implantation-bleeding\/\" target=\"_blank\" rel=\"noopener noreferrer\">implantation bleeding<\/a>&#8221; and which can be confused with abnormal menstruation, although there are differences between them.<\/p>\n<p>In any case, the only reliable way to know if the embryo has implanted is to perform a blood test that will reveal the amount of beta-hCG hormone in the patient, approximately 10 days after the transfer. Depending on the values of this hormone, also known as &#8220;the Beta&#8221; or &#8220;the pregnancy hormone&#8221;, we will be able to confirm pregnancy.<\/p>\n<p>If you want to undergo an assisted reproduction treatment and you have questions about embryo transfer, the embryo implantation process or other related issues, please <a href=\"https:\/\/www.juanacrespo.es\/en\/contact\/#citaprevia\" target=\"_blank\" rel=\"noopener noreferrer\">contact us<\/a>. We will be happy to answer your questions.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>The embryonic implantation is the process by which the embryo, already transferred into the mother&#8217;s uterus, attaches to  [&#8230;]<\/p>\n","protected":false},"author":1,"featured_media":29349,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"content-type":"","footnotes":""},"categories":[66],"tags":[],"class_list":["post-32768","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.old.juanacrespo.es\/en\/wp-json\/wp\/v2\/posts\/32768","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.old.juanacrespo.es\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.old.juanacrespo.es\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.old.juanacrespo.es\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.old.juanacrespo.es\/en\/wp-json\/wp\/v2\/comments?post=32768"}],"version-history":[{"count":1,"href":"https:\/\/www.old.juanacrespo.es\/en\/wp-json\/wp\/v2\/posts\/32768\/revisions"}],"predecessor-version":[{"id":32770,"href":"https:\/\/www.old.juanacrespo.es\/en\/wp-json\/wp\/v2\/posts\/32768\/revisions\/32770"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.old.juanacrespo.es\/en\/wp-json\/wp\/v2\/media\/29349"}],"wp:attachment":[{"href":"https:\/\/www.old.juanacrespo.es\/en\/wp-json\/wp\/v2\/media?parent=32768"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.old.juanacrespo.es\/en\/wp-json\/wp\/v2\/categories?post=32768"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.old.juanacrespo.es\/en\/wp-json\/wp\/v2\/tags?post=32768"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}