Age and Success Rates for IVF and FET

The following graph is taken from a summary report Assisted Reproductive Technology in Australia and New Zealand 2016, published September 2018 and available at https://npesu.unsw.edu.au/surveillance-reports.
Thaw cycles refer to embryo transfer using embryos which have been frozen and then thawed, or what we call a frozen embryo treatment cycle (FET). See section Success Rates>IVF Success Rates for fresh cycle data.
The report uses the term ‘autologous’ which simply means that the embryos result from the use of the patient’s own eggs/oocytes. Therefore it does not include donor oocyte cycles. However, an autologous cycle can include either the male partner’s sperm or donor sperm.

The graph shows the success rates (live births) for IVF (autologous fresh) and FET (autologous thaw) cycles divided into age ranges. This is based upon the woman’s age when the cycle started.

As noted in the section Success Rates>FET Success Rates, FET is more successful than IVF because some of the problems which can occur such as no fertilisation, no eggs collected and freeze-all cycles have been bypassed, and therefore more FET cycles progress to embryo transfer and live births.  A contributing factor is also that the patient’s age for FET is older than the age of the embryo.  For patients who have had a long break between the initial IVF cycle which produced the embryos and starting the FET cycle this can be significant.

It is obvious from the graph above that there is a significant decline in success rates after age 35 years.

It is interesting that the age group less than 25 years has much lower success for IVF than for women aged 25-30.  This may be because women under 25 years who undertake IVF are likely to have more severe fertility conditions and therefore consider IVF at this young age.