After three years of running this site, we have fielded dozens of questions about IVF Success Rates. Here are some of the most popular ones. Have a question that isn't here? You can ask it in the comments section and we will do our best to get it answered.
Why are the most recent published success rates on SART two years old and on CDC three years old?
IVF success rates are based on live births and counted in the year the IVF cycle was started not the year of birth. For example, if a woman had a successful IVF cycle in December, SART gets the IVF success data from fertility clinics at the end of the following year, and counts that woman's baby as a successful IVF case for the previous year. Because of popular demand, SART started to publish this data on their website a few years ago. However, the SART data is not verified by any third party agency. The Center for Disease Control (CDC) and other Government offices take about 12 months to verify, analyze and compile the data and publish the verified fertility success rates in the first quarter of the new year in the ART (Assisted Reproductive Technology) section of the CDC's website. The CDC is three years old at the time it is published.
Why do you compare the life birth rates than pregnancy or implantation rates?
As an example, in 2005 there were 97,442 IVF cycles using fresh embryos across all age groups. Of those cycles, 34% got pregnant, but only 28% carried the baby to term and gave birth. That's a big difference! This site was built for IVF patients. Most of them want to know the chance of taking home a baby.
IVF doctors like to present you success rates based on pregnancies or even implantation rate. Pregnancy rates are based on a positive pregnancy test result in the first trimester. Implantation rates don't even factor in a pregnancy test. Both Implantation Rate and Pregnancy rate are going to be higher than the Live Birth Rate, that's why doctor's quote them so much. You, as a patient, however, want a baby. So we rate the clinics compared to Life Birth Rate.
Why do SART and CDC make it difficult to compare IVF success rates?
Good question. We have a separate post about that controversial rule here.
Still have unanswered questions about IVF success rate data? Great! Post them in the questions and we will do our best to get you an answer.
Hi there,just wondering why you do not use the “over 42” category but do show the other rates? For ex,when I search 41-42 the clinic I use is at the bottomof the ratings,but the SART data show that my clinic is the top clinic for over 42. If I had followed this site’s advice I would have gone to a clinic that isactually the worst for 42 and over. I hope you will consider including this age group as I imagine other women are similarly misdirected otherwise. 🙂
Hi Allie: Thanks for the question. For success rates to be statistically significant, ASRM guidelines specify that there must be more than 21 cycles in a group.
This is why you see so many statistics for the oldest age group reported in a format like 3/9 where there are three successful cycles out of 9 total cycles.
In this example, you could say the clinic has a 33% success rate but this isn’t very reliable considering there were only 9 total cycles.
We don’t report success rates where there aren’t more than 21 total cycles. This means that in most states we wouldn’t have any data to report in this age group.
What we may do is compile a list of all clinics in the United States that have > 21 cycles in the oldest age group in a special report.
Thanks again for your question.