Difference between Embryo Transfer and Embryo Implantation

Both the terms might sound the synonym of each other but are entirely different methods because one is a natural biological process while another is an artificial method performed during IVF cycle. Both are two dissimilar processes of a single IVF cycle. 

Embryo Transfer is a medical procedure of transferring embryo into the uterus using embryo transfer catheter (a plastic hollow tube), while Embryo Implantation is a biological process performed by reproductive system to implant the embryo into uterus lining.

In an IVF cycle, both Embryo Transfer and Embryo Implantation are consecutive process, where the transfer takes place first and then the implantation. Only after the transferred embryo implants, it will result in a pregnancy. For a patient to understand Embryo Transfer is the transfer of embryo artificially prepared outside the body into uterus, so it depends on the skills and experience of a doctor while Embryo Implantation, on the other hand, is an in-utero biological process which is not in control of the doctor.

The embryo is implanted in three biological steps, namely apposition, adhesion and invasion. It depends on hormonal and molecular activities inside a uterus to control these steps. No experimental method can control these steps as it is a biological process cannot be controlled externally. 

A doctor cannot guarantee the implantation as it is totally the hormonal activity. Also, the dietary habits, environment or stress have no impact on these processes. The women need to be patient and wait for two weeks for the HCG test to tell whether the implantation happened or not.

It might happen that the embryo does not implant, which results in the failure of IVF cycle. It is not possible to detect the exact reason behind the failure of implantation, but several possibilities like abnormality in embryo or eggs of the older are considered if the cycle fails.

For realistic understanding, the failure of embryo implantation after the body rejects the embryo does not mean that the IVF lab used some wrong methods for embryo transfer. Response of the human reproductive system to a particular external process cannot be predicted. Patients need to have rationale understanding and clear idea about the difference between both the methods. 

Dr Neeraj Pahlajani