Recurrent implantation failure (RIF) means seemingly good-quality embryos have been transferred over multiple IVF cycles without a pregnancy resulting. Implantation is the step where the embryo attaches to the uterine lining. It is the part of IVF that doctors can least directly control. That is why, when it keeps not happening, it gets its own careful re-check.
What counts as recurrent implantation failure
There's no single agreed number. It's usually raised as a concern after several transfers of good-quality embryos, often at the blastocyst stage, don't result in a pregnancy — especially when the embryos look sound. The exact transfer count matters less than the pattern. A pattern like this should be investigated, rather than repeating the same approach unchanged.
What the workup investigates
Investigation works through three areas:
- The embryo — chromosomal status, which becomes more significant with age; genetic testing (PGT) may be discussed if it hasn't already been done.
- The uterus — polyps, fibroids, adhesions, or chronic endometritis inside the cavity, often checked directly with a hysteroscopy since it can catch things an ultrasound misses.
- The endometrium's receptivity — its thickness, and whether the transfer is timed to when your lining is ready to accept an embryo.
Blood conditions affecting clotting or immunity are also considered as part of a broader work-up.
When it's raised after transfers
This check usually comes up after repeated transfers haven't worked, even though the embryos looked good on grading. It is a planned pause to ask "what haven't we checked yet?" It is not raised after a single failed transfer. If you've had pregnancy losses, rather than embryos not implanting at all, that's a related but different pattern covered under recurrent pregnancy loss.
For the full workup — what each test actually checks, what happens once a cause is found, and the honest outlook when none is — see the complete guide to recurrent implantation failure.
The outlook
RIF is frustrating because each attempt looked right beforehand. But a careful re-check often finds something that can be changed. Many couples with RIF do go on to a successful transfer once the cause is found and treated.
Frequently asked
What is recurrent implantation failure?
It's when embryos that look good on grading repeatedly fail to implant after being transferred across multiple IVF cycles. This calls for a closer look at the embryo, the uterus, and the timing of the transfer, rather than simply repeating the same treatment plan.
How many failed transfers before it's called RIF?
There isn't one fixed number used everywhere — it's a clinical judgment based on how many good-quality embryos have been transferred without success, not a single failed attempt.
What tests are done to investigate recurrent implantation failure?
Common steps include a closer look at embryo quality or genetics, a hysteroscopy or imaging to check the uterine cavity, an assessment of the endometrium's thickness and receptivity, and blood tests for clotting or immune factors, depending on your history.