Caution: Infertility Treatment Success Rates Can be Misleading

For all patients, gauging the chance of success of their infertility treatment is a critically important component of the process. It is important for us, as well, to be certain that our patients have realistic expectations of their treatment. In order to assure accuracy, any estimation of the expectation of success should be highly individualized. For many patients, the use of average rates will be misleading, since numerous factors impact treatment outcomes. As an example, consider the IVF data presented below. This chart shows the accumulated IRMS delivery data from the past 10 years, as reported to the CDC ( The data were compiled from almost 7500 treatment cycles – the number of cycles in each group is shown at the top of the column. The chart illustrates significant variability in pregnancy rate according to only one factor – patient age.


While an important message emerges from this information – that pregnancy rates decrease with increasing age – it is important to remember that each column itself represents only an average pregnancy rate. Each of these groups is composed of patients with a variety of indications for their infertility, and correspondingly different expectations of pregnancy. Some other factors that are very important in the determination of success are diagnosis, years of infertility, genetics, male partner issues, and ability to respond to agents used for ovarian stimulation. So, it is important for each patient to obtain an individualized assessment of their pregnancy prognosis, provided by a reproductive endocrinologist, as they make their family-building decisions.

The Society for Assisted Reproductive Technology, to which we belong, requires that we include the following statement in our discussion of pregnancy rates: “A comparison of clinic success rates may not be meaningful because patient medical characteristics, treatment approaches and entrance criteria for ART may vary from clinic to clinic.”