What is a truly RIF Individualized definition of RIF.

Repeated failure of ART is still considered a major challenge in infertility treatment. The success rate after IVF depends on several factors including the patient’s medical characteristics (age,AMH…) and various indications and treatment protocols used for ART in different infertility clinics. Therefore the dynamic nature of success rate affects the clinically challengeable definition of RIF. For example, if the average implantation rate (IR) is presumed to be 30% , more than 6 embryos should be transferred so that a pregnancy rate(PR) of 90% could be achieved. meanwhile, if the calculated IR is 40% ,the same PR could be occurred by transfer of only 4 embryos.In patients with less predicted IR, number of cycles or embryos needed for a reasonable pregnancy rate is certainly more. This formula ( log [0.7]*0.1 vs log [ 0.6 ] *0.1) provided by Bentove et al , makes it possible to calculate the number of required embryos for each patient so that PR remains 90% and the other 10 % of patients who would not conceive ,are considered as truly RIF ones. The log base represents the likelihood for a failed implantation and 0.1 represents 10 % patients who will not conceive. Therefore, based on any patient’s medical history and IVF success rate in a special infertility clinic, RIF should be individually defined for each patient. Attention to individualized definition of RIF, gives the opportunity to calculate the actual number of required cycles more reliably and recommend the most proper approach to each patient.

کلیدواژه ها:

IVF ، Implantation ، repeated implantation failure ، success rate ، definition