Intralipid with iui when does the implantation take place

Implantation in the uterus

Implantation is the moment when an embryo is implanted in the lining of the uterus. Pregnancy does not begin until the fertilized egg cell has implanted. It occurs about five to ten days after the egg cell is fertilized.

Pregnancy begins with implantation

Only after implantation does the embryo come into direct contact with the maternal bloodstream. Only then is the pregnancy hormone produced and can be determined with a pregnancy test. This hormone is called hCG (human chorionic gonadotropin) and the corresponding tests in the urine or from the blood can detect this.

It is not possible to tell whether the implantation has taken place or not. Occasionally, light bleeding or spotting occurs a few days after ovulation. This can then be an implantation bleeding, a possible indication of an implantation.

Symptoms of implantation.

There is certainly a situation in which one knows pretty much exactly when ovulation should take place. The time period can be narrowed down by measuring temperature curves and other methods of natural family planning (NFP)1)RaithPaula, E. "Natural family planning in the case of and unfulfilled desire to have children."Natural family planning today: Modern cycle knowledge for advice and application(2013): 153.

Therefore, the body is then observed much more closely and there are women who seem to feel their ovulation. With implantation, however, it is much more difficult. Again, there have been reports of pulling and pinching of the lower abdomen, but these signs of implantation are unreliable. This also applies to the already mentioned implantation bleeding, which can also have other reasons.

Shortly after the embryo has implanted in the uterus, the formation of the pregnancy chromone hCG begins. First of all, the blood levels of this hormone are very low. In the days after implantation, however, the first signs of pregnancy can occasionally appear.

Development of the egg cell up to implantation

After fertilization in the fallopian tube, the fertilized egg cell is transported through the fallopian tube towards the uterus. During this time, the embryo develops into a blastocyst through several cell divisions after 5-6 days.

Only at this stage can the embryo implant itself. In the blastocyst, the cells specialize in certain functions. You can see the cells that will later develop the actual embryo (embryoblast), those that will become the placenta (trophoblast).

This blastocyst is still in the original egg shell ("zona pellucida"). Shortly before implantation, the embryo expands and the egg cell shell is severely thinned ("expanding blastocyst"). Shortly afterwards, the embryo leaves the egg shell ("hatches") and can only then implant itself2)Würfel, W. "The early embryo."Gynecological endocrinology 13.2 (2015): 92-97.

When exactly does implantation take place?

All these processes take about six days from ovulation. only then has the embryo "hatched" and implanted. In principle, you can also calculate this yourself. If you know the time of ovulation, fertilization will take place the day after. A further five to six days then pass, after which the embryo implants.

What happens if there is no implantation?

Even if the embryo develops normally until shortly before the time of implantation and then has contact with the uterine lining, implantation is not guaranteed. In these cases, what happens to all dead cells in the body happens to the dead egg or embryo: they are disposed of by immune cells.

So you don't have to have the idea that the embryos would be recognizable when the menstrual period takes place. At this point, they are no longer there.

The implantation process

The two partners of implantation are the uterus with the maternal immune system and the embryo. The exact processes involved in implantation have not been adequately researched and, in particular, the importance of the immune system has largely not yet been clarified. After all, the embryo is a foreign body and implantation is an invasive process, similar to that of malignant diseases. The maternal defenses must recognize that the pregnancy should not be fended off3)Markert, Udo R. (Ed.): Immunology of Gametes and Embryo Implantation. Basel, Karger 2005. 205 p. With 10 figures and 8 tables.

Numerous messenger substances (especially "cytokines") are sent back and forth between the embryo and the uterine lining until implantation takes place in an optimal location. The embryo penetrates the mucous membrane and begins to grow into it and make contact with the maternal blood system4)Niakan, K. K., Han, J., Pedersen, R. A., Simon, C., & Pera, R. A. R. (2012). Human pre-implantation embryo development.Development139(5), 829-841..

In addition to the immune system, blood circulation is also of great importance here. Very fine vessels develop, the blood flow of which can be restricted by coagulation disorders. Quite a common cause of early miscarriages.

At this stage, small amounts of pregnancy hormone enter the maternal bloodstream for the first time and can be detected there. The pregnancy hormone supports the production of corpus luteum homomones and this prevents further cycles or even ovulation during pregnancy.

Is it possible to encourage implantation?

It's not sure what factors are causing the Can improve implantation. A healthy lifestyle is certainly one of them. A balanced diet rich in vitamins and sufficient exercise can certainly help.

But there are also many tips on the Internet that you should avoid in order not to disturb the implantation - especially after an artificial insemination. We have summarized these in our article "13 Tips on Behavior After Transfer".

Ultimately, unfortunately, one has to accept that implantation cannot be forced, but depends on factors that we cannot all influence. So it always takes a bit of luck if you want to get pregnant.

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((Ludwig Bispink, Elmar Breitbach, and Norbert Schlote Practical Fertility Diagnostics - Uni-Med, Bremen (2011))) ((Freimut A. Leidenberger (Editor), Thomas Strowitzki (Editor), Olaf Ortmann (Editor) Clinical Endocrinology for Gynecologists - Springer; edition: 5th edition 2014)) ((Michael Ludwig, Frank Nawroth, Christoph Keck fertility clinic - Springer; edition: 3rd edition 2015 (April 13, 2015))) ((Ludwig, M. (ed.) (2010): Gynecological endocrinology and reproductive medicine. Current topics from gynecological practice. Munich.))