Egg, Sperm and Embryo Quality
Egg, sperm and embryo Quality are one of the most important factors that can affect implantation. When there are genetic abnormalities in eggs, sperm or embryo, these are less likely to develop normally and to implant in the uterus. These genetic abnormalities changes can be a result of age or lifestyle and habits.
Endometrial Receptivity
Endometrial receptivity occurs 6 days after the post-ovulatory progesterone surge and lasts about 2 to 4 days. However, in some women, the receptivity window is displaced, occurring a few days before or after that expected period. If embryos are implanted outside the woman's endometrial receptivity window, implantation will not occur.
Hormones
Hormonal or metabolic disorders, like low progesterone levels, uncontrolled diabetes, thyroid disease, and variations in the prolactin levels can affect implantation of the embryo in the uterus.
Anatomical changes
Changes to the anatomy of the uterus, the presence of septums, endometrial polyps, uterine fibroids, adhesions, hydrosalpinxes, and endometriosis can affect implantation.
Lifestyle and habits
Unhealthy diets, smoking, or practicing vigorous exercise can affect embryo implantation.
Failed implantation can be due to one of these factors, or it can be multifactorial - where many of these are affecting implantation. If you have experienced failed implantation after embryo transfer, it is important to discuss with your doctor to see what might have caused it, whether any tests can be done and what the next steps will be in your treatment.