Understanding IVF success rates doesn’t have to be difficult
Most patients considering in vitro fertilization (IVF) want to know the likelihood that the process will end with a healthy baby. One of the first places many people look for IVF success rates is the Society for Assisted Reproductive Technology (SART), which tracks fertility centers’ success rates with different IVF procedures.
While SART data reflect each clinic’s track record of success, they cannot predict your personal outcomes from IVF. Afterall, each patient is unique. As such, our Las Vegas infertility doctors can tell you your approximate chances of success based on your age, diagnosis, procedure and any other relevant factors.
What are the most valuable measures of a center’s success rates?
The most valuable measures of a center’s IVF success rates are its live birth per patient and live birth per embryo transfer data. For both these measures, our IVF success rates are consistently higher than the national average, across all age groups.
The above rates count all the following as failures.
- Any patient or couple who produced no eggs or embryos.
- Any patient who had embryos but did not return for an embryo transfer within one year of their retrieval date, regardless of their eventual outcome.
- Any patients who had their embryos shipped to another center for transfer, regardless of outcome.
- Patients who had an embryo transfer but did not have a live birth.
- Any patient who had a transfer and a pregnancy but could not be reached later to confirm live birth.
Therefore, the true success rates per patient or per cycle are probably higher than shown.
When viewing per-transfer success rates, keep in mind that these statistics exclude patients who started the IVF process, but never underwent an embryo transfer. This means these figures will be higher than birth rates per cycle start.
What else should you consider when reviewing IVF success rates?
Clinical methods, laboratory equipment, clinician experience and skill, and the patient population can all affect SART data. As a result, when comparing SART data for clinics, be sure that you are comparing “apples to apples.” For example, age is an important factor. As such, success rates for IVF (without donor eggs) in women under 35 are higher than those for women over 40.
There are several other important factors to keep in mind when comparing IVF success rates.
- Single vs. multiple embryo transfer. The best centers have high pregnancy and birth rates with single embryo transfers. Some clinics transfer multiple embryos to boost their success rates, but this practice increases the chance of having a risky twin or triplet pregnancy.
- Own eggs vs. donor eggs. Some centers have patients with diminished ovarian reserve move forward using IVF with donor eggs. These clinics may have artificially higher success rates by declining to treat patients with a poor prognosis.
- Egg donor cycle rates. Donor cycle success rates measure the clinic’s performance in an ideal case. While this rate might not directly apply to patients not using a donor, it does give the clearest available measure of the clinic’s and lab’s performance when most effects of patient variability are removed. It also offers the most reliable method when comparing clinics because the egg donor medical criteria for selection is the same nationwide.
There can also be invisible factors behind the numbers. A failed cycle in SART data could have many causes unrelated to the quality of the fertility center. For example, a failure could occur if a woman doesn’t respond well to medications and her IVF cycle is cancelled. It could also occur if the clinic does not transfer any embryos, due to genetic testing results, or if none of the embryos produced are the sex the couple wanted.
What’s the difference between preliminary and final SART data?
Timing is also a factor. The latest SART data are “preliminary” because they are not complete. This preliminary report is biased because it counts all failures immediately and specifically excludes successful transfers that occurred in the following calendar year and resulted in pregnancy. This negative bias is greatest for centers that tend to freeze all embryos. The “final” SART reports take one year longer to produce, but are less biased, especially for clinics like FCLV that do only frozen transfers. In one year, our preliminary live birth rate was 44%, but increased to 58% when the final report for that year was published.
To learn more about our IVF success rates or to schedule a personal consultation with one of our Las Vegas infertility doctors, contact us.