Recurrent Implantation Failure (RIF): Why Do Good Embryos Not Stick?

What is RIF? Generally, RIF is diagnosed when a woman has had 3 or more high-quality embryo transfers (or transfer of at least 4 good-quality embryos in multiple cycles) without achieving a clinical pregnancy. Implantation relies on a complex dialogue between a healthy embryo and a receptive uterus. If it fails, the problem lies with one or the other — or their interaction. 1. The Embryo: Genetic Abnormalities The most common cause of implantation failure is a chromosomally abnormal embryo (aneuploidy). Even embryos that look 'Grade A' under the microscope can carry genetic errors that halt their development shortly after transfer. Solution: Preimplantation Genetic Testing (PGT-A) to transfer only euploid (normal) embryos. 2. The Uterus: Structural Issues Polyps, submucosal fibroids, adenomyosis, or intrauterine adhesions (Asherman's syndrome) act like physical barriers or create a hostile environment. Solution: A diagnostic hysteroscopy allows us to see inside the cavity and correct these issues directly. 3. The Uterus: The Receptivity Window The endometrium (uterine lining) is only receptive to an embryo for a brief 24-36 hour 'window of implantation.' For about 25-30% of women with RIF, this window is displaced (earlier or later than usual). Solution: The ERA (Endometrial Receptivity Analysis) test determines your exact window, allowing for personalised embryo transfer timing. 4. Undiagnosed Infections (Chronic Endometritis) A silent, low-grade bacterial infection of the uterine lining (chronic endometritis) causes inflammation that prevents implantation. It has no obvious symptoms. Solution: Uterine biopsy (ALICE test or pathology) and targeted antibiotics. 5. Immunological and Clotting Issues Overactive natural killer (NK) cells or undiagnosed blood clotting disorders (thrombophilias) can prevent the embryo from establishing a blood supply. Solution: Comprehensive blood tests and treatments like blood thinners or immunosuppressive protocols.