What is implantation and what causes it to fail?

Implantation is the stage wherein the embryo attaches to the uterine wall and is vital for positive detection of pregnancy. In case of failure to implant, the pregnancy fails, and the couple will have to restart their IVF cycle. In case of three consecutive failures of IVF cycles with good quality embryos, the individual is known to have been diagnosed with recurrent implantation failure.

This will require a deeper evaluation and understanding of the causes of failure, including – anatomic assessment, uterine environment testing, testing for blood clotting and genetic testing, and others. This is to understand the underlying causes of failure accurately and to take necessary corrective measures.

However, it is essential to note that every case of recurrent implantation failure may not have an attributable cause.

Is there a window of implantation?

Yes. For successful implantation, the embryo should be at the right developmental stage and the uterus must provide a hospitable environment. This is known as the window of implantation. While there was a traditional view that all women had the same window of implantation, viz., about 8-10 days after ovulation. However, recent advances in fertility science have improved the understanding of the window of implantation and it is now understood to be specific to individuals. This is due to the variances in the uterine environment, and thus the window of implantation is now a little more fluid than in the earlier days.