Implantation failure is a part of the in vitro fertilization procedure that is not very well understood because patients succeed to produce healthy embryos but at the implantation phase things go wrong for inexplicable reasons.
It is defined as the embryo’s failure to implant during the IVF cycle, but not all the specialists agree with this definition. Some of them consider that implantation failure represents the failure of achieving a pregnancy after several IVF cycles. Other doctors compare the number of embryos which were transferred with the number of treatment tries. There are three main causes of IVF implantation failure:
For several years it was believed that the best time for embryo transfer was in the third day after the egg retrieval. There are embryos that look very good in the third day, but they might lead to implantation failure afterwards. On the other hand some embryos might look poorly in the third day but they can develop very well by the fifth day. That is the reason for which blastocyst transfer appeared.
Another issue is the embryo’s hatching. Before the implantation can start the embryos has to get out of its shell and afterwards make contact with the uterus cells. It is believed that implantation failure can be caused by the fact that the embryo is not able to hatch from its shell. That’s why the concept of assisted hatching was introduced. The assisted hatching “helps” the embryo by creating a small opening in its shell. However the risk of identical twins appears along with this technique due to the fact that the embryo can divide easily when its shell is removed. So the assisted hatching remains at the stage of experiment in treating IVF implantation failure.
Studies show that the toxins coming into the uterus from infections (current or previous) have a high impact on embryo implantation. It is very difficult to determine the cause of the infection. Some doctors take a sample from the uterine cavity using a catheter inserted through the vagina and the cervix but this is not a very efficient way because the catheter could collect bacteria from the cervix and the vagina not only from the uterine cavity. Other specialists treat the uterine infection with antibiotics when the correct antibiotic can be precisely identified.
Other problems that can appear within the uterus environment are anatomic abnormalities that prevent implantation mechanically like tumors of the uterus wall or outgrowths of the uterus lining and so on.
The uterus lining has to respond well to estrogen and progesterone in order to have a successful implantation. Although this is a rare occurrence, we have to mention that implantation failure may also be caused by medical negligence, which is why you have to make sure you get the best, most attentive doctors, and that you understand the procedure enough yourself to tell when something goes wrong. If you feel like you might have been the subject of medical negligence, check out Medicalclaimsguide.com and see what you could do to correct your situation, or at least get the compensation you deserve.
-interaction between the uterus and the embryos
Both the uterus and the embryos have to be receptive to implantation. The uterus lining secrets cells called cytokines that ensure the interaction between the embryo and the mother. The uterine lining secrets also immune cells. Before the implantation the uterine lining is preparing by simulating expression of the adhesion systems that will hold the embryos to the uterus. The immune cells are the ones who send the signal to the uterus to simulate the adhesion. If this doesn’t happen then the implantation failure will occur.