Success Rates – What You Need To Know
An important factor when it comes to choosing an IVF center is their success rates. Patients want the best chance for success so they look for centers that have high success rates. However, these rates can be confusing and it is important that you understand how to interpret them. First you want to look for clinics that are performing a substantial number of IVF cycles a year. Typically 200 or more total IVF cycles or more per year is an adequate amount to determine success rates by age group. When a clinic has a small number per age group success rates will vary greatly based on a difference of only one or two pregnancies, which can be misleading.
Success can vary due to many factors. Age is the most important factor, when women are using their own eggs. Success rates decline as women age, and success rates drop off even more dramatically around age 37. Part of this decline is due to a lower chance of getting pregnant from ART, and another part is due to a higher risk of miscarriage, especially over age 40. However, there is no evidence that the risk of birth defects or chromosome abnormalities (such as Down syndrome) is any different with ART than with natural conception.
Success rates vary with the number of embryos transferred. However, transferring more embryos at one time does not continue to increase the chance of success, but may only increase the risk of a multiple pregnancy, which is much more complicated than a singleton pregnancy and is more likely to result in babies with severe medical problems.
Day 3 follicle-stimulating hormone (FSH) levels are also critically important in evaluating your potential for successful conception in an assisted reproductive technology program. This blood test is typically drawn on the third day of a woman’s menstrual cycle. Day 3 FSH levels have been shown to be an incredibly accurate predictor of IVF success, independent of age. Essentially, an elevated Day 3 FSH value indicates a very poor prognosis for conception through IVF and a high risk of pregnancy loss should the rare conception occur. Every IVF program establishes a “threshold” FSH value unique to their laboratory, above which pregnancies are very rarely conceived despite great effort and repeated IVF attempts. At RMA, we have determined that an FSH value of 15 or higher predicts that IVF will have little or no chance in helping to achieve pregnancy.
The Society for Assisted Reproductive Technology (SART) is the primary organization that collects cycle data and creates guidelines and standards for the centers to follow. Visit SART’s website at www.sart.org to get more information and review the most recent 2010 success rates.