Symptoms of embryo implantation

From the moment the egg is fertilized until the baby is in our arms, we live a whole process, both internal and external, that leaves indescribable sensations. One of these stages is the moment of implantation of the embryo in the uterus, a very important process in fertilization treatments.

Embryo implantation is a key phase in the pregnancy process , whether spontaneous or through in vitro fertilization or assisted reproduction treatments, because if it is not successful there are no chances of gestation. Well, even if there is a fertilized egg and the embryo makes its way through the fallopian tubes without problems, being able to reach the endometrium, if it does not manage to nest in the wall of the uterus, nothing can be done. This phase is so important that if the new being is not implanted in the uterus, it could not receive food and shelter during the entire gestation.

In this post, we are going to try to clarify some doubts that are generated around this first phase of pregnancy, explaining the process of fertilization and formation of the embryo during this stage.

Where does fertilization occur?

The first thing you need to know is when your ovulation occurs; And if you do not keep track of your menstruation, it would be very useful to use some of the ovulation tests that are sold on the market, or opt for some home method to help you. In this sense, once ovulation has occurred, that is, when the egg is expelled from the ovary, it begins to travel through the fallopian tubes (which is where the fertilization of the egg occurs) waiting for a sperm, this journey lasts between 12 and 24 hours. If this male gamete reaches the egg and fertilizes it, then that process of implantation of the egg would begin.

Now, the sperm can last up to 6 days inside the female uterus, so fertilization does not occur immediately when having sexual intercourse, so we could not know if something is noticed when the egg is fertilized. In any case, what we do know is when the symptoms of pregnancy begin.

How long does it take for the egg to reach the uterus? 

It is important to know that once the fertilized egg takes between 6 and 12 days to reach the uterus, being directed by the cilia and this process is known as implantation, which is the fixation in the uterus of the already fertilized egg so that viability exists. of pregnancy. During this journey, the ovule begins to divide and forms different structures.

When does embryo implantation bleeding occur?

Naturally, the implantation process occurs between 6 and 7 days after the egg has been fertilized, and is completely painless. This is when the embryo begins its fusion with the inner uterine layer, called the endometrium. Firstly, the embryo is implanted and later, it begins its development in the mother’s womb.

In general, the woman does not have any signs during this phase, but it can happen that there is a small bleeding during those days being associated with implantation symptoms, which is known as implantation bleeding. 

Now, this bleeding occurs because on certain occasions, in the process in which the embryo is being implanted in the uterine wall, the endometrial tissue tends to erode and this produces a slight bleeding that, coincidentally, will coincide with the date of your birth. menstruation and for this reason, many women often confuse it with their period. But you should know that during implantation, your body will produce chemical signals to prevent your period from coming.

Among the possible symptoms that a woman may feel during this stage, we can mention:

• A slight but persistent headache; 
• Your breasts swell and you feel some pain; 
• Mild cramping in the abdominal area;
• A pink or brown vaginal discharge;
• Drowsiness and tiredness.

Thus, if you are wondering what implantation bleeding is like, you might notice that you have brown spotting or in some cases red, on those days when embryo implantation is taking place and a sensation as if your period is coming.

How long does implantation bleeding last?

As we have already mentioned, this bleeding is not profuse, on the contrary, it is quite light and could last between 1 and 3 days. It’s probably a darker color than your usual bleeding, or it could just be a single drop of blood and that’s it.

embryo growth

Once the egg has been fertilized by a sperm, it begins to divide into 2 cells, to go progressively dividing into 4, 8, 16 cells and so on, until it becomes a morula, around the fourth day of life. embryo. The morula is a small compacted mass of stem cells that make up the embryo, until it reaches its 5th day of life, in which it becomes a blastocyst and already has many cells, beginning to transform into an embryo.

After this fifth day, the embryo prepares to break its membrane and come out of it to implant itself in the endometrium, this process being between the 6th and 7th day. However, in this process the exact moment in which implantation occurs cannot be determined, because each embryo has its own rhythm. But, if after days 7 and 8 the embryo failed to implant, then it is likely that this process no longer occurs. In the case of not implanting the embryo, then your body will absorb that non-viable embryo and it will disappear.

Now, a 4-week gestation embryo is already 2 weeks old, but it still doesn’t look human; however, already at this stage some protuberances begin to be distinguished that will later become the head, body and arms of the future baby. In addition, in this phase the neural tube will be formed, the spinal cord that will integrate its central nervous system and the placenta, the organ through which the baby will feed and receive oxygen. 

After 14 days of the fertilization process, you should already be sure that the embryo has implanted in the uterus and is firmly nested in what will be its home for the next 9 months.

In short, the entire process of development and growth of a baby from the time it is fertilized until it is born is wonderful, being these first days after fertilization very important for the process of implantation of the embryo in the mother’s uterus; so we hope that this post will serve as a guide to learn a little more about your pregnancy. But remember that if you have any questions or queries, it is best to go to your trusted gynecologist.