Our specialist team are passionate about helping you achieve your dream of taking home a healthy baby. The chances of success in each treatment cycle, is very much dependent on the client’s own set of personal characteristics such as cause of subfertility, reproductive history, lifestyle factors and most of all the woman’s age. Each and every cycle of treatment is therefore thoughtfully tailored to each client to achieve the best possible results. Because everyone’s chances of success is different, the presentation of average rates can be misleading and comparing rates between clinics meaningless. You can be assured that the clinics in New Zealand are all operating to the highest industry standards, so your choice of clinic will ultimately depend on the best fit and feel for you. The live birth outcomes that are presented below, represent the most current average rates of success for IVF/ICSI fresh and frozen cycles based on all Australian and New Zealand clinics.
The four most important things you need to know about success rates are:
- The fertility clinic you are planning to attend is operating to the highest clinical standards
- How age of the woman and her ovarian reserve affects the chance of success
- How success rates are presented in different ways
- How lifestyle factors can affect success
1. The fertility clinic is operating to the highest clinical standards
All clinics in New Zealand and Australia are required to report their live birth success rates to authorities (ANZARD) that analyse and publish the results so that clinics can benchmark themselves against acceptable clinical standards. The results for Repromed are assessed by our external auditors GlobalMark on behalf of the RTAC (Reproductive Technologies Accreditation Committee) and the New Zealand Ministry of Health (NZ8181 Guidelines). Additionally, clinics such as Repromed who provide publically funded treatment, are also performance monitored 6 monthly by their Regional Health Authority. The endorsement of these authorities provide an assurance to patients, that they are receiving the highest level of quality of care and outcomes.
2. How the woman’s age and her ovarian reserve affects the chance of success
It is well accepted that the woman’s age is the most significant factor that influences the chance of success. This is because a) the number and b) the normality of her eggs decreases with age. From the table below you can see that women under the age of 35 have the highest chance of a birth while the most common age group who seek IVF treatment, the 35 to 39 year olds, have a 23% rate of having a baby. Importantly, livebirth rates in women 40 years and older, dramatically decline to just 8% per treatment cycle in fresh and 14% in frozen embryo transfer cycles. The ovarian reserve (the number of eggs in the ovary) of women is related to success and is measured in an AMH blood test. Women of any age who have an AMH of less than 5 pmol/L have a significantly lower rate of having a livebirth. This is because they generally have fewer eggs retrieved and less embryos available for freezing in an IVF cycle regardless of the amount of hormone stimulation they take. As women get older, the number of eggs that are genetically normal, also go down and are less likely to create a pregnancy that results in a normal healthy baby (see graph below). For these reasons, it is important that success rates are always presented in a graph or table that breaks the results down into women’s age groups.
In addition to age, there are a number of variables that will influence you taking home a healthy baby. Your individual chance of success should be discussed with a fertility doctor during your first consultation.
The success of donor insemination cycles are slightly higher than those shown in the graph above for IUI cycles due to a lower incidence of infertility factors in women undergoing DI, in addition to the high quality of the donor sperm.
Many women undergoing ovulation induction are reliant on the ovarian stimulation medications to induce ovulation, and once this has been achieved, their chance of success is similar to a fertile couple attempting to get pregnant each month over a 12 month period.
3. Understanding the differences in reporting
It is important that clients understand there are many different ways results are being presented in the media and on clinic websites which calls for caution when interpreting them. To give you an idea of what this means, refer to the graph below which shows the progression of results that are reported based on the different stages of treatment.
Read more about understanding success rates in this helpful document from the Fertility Society of Australia’s website: How to choose an IVF clinic and understanding success rates.
Important points regarding success rates:
- Live birth is the most meaningful outcome, because not all clinical pregnancies (heartbeat seen at 7 weeks) will result in the birth of a baby due to miscarriages (approx. 23%)
- Pregnancy rate is interesting but not a recommended outcome as it can be easily misleading for patients who at the end of the day just want a live healthy baby. Clinical pregnancies are reported as a fetal sac or fetal heartbeat seen on ultrasound at 7 weeks of pregnancy.
- Number of embryos transferred can influence the results, as the more embryos are transferred, the greater the chance of pregnancy and twins. The standard practice in most clinics in Australia and New Zealand is to transfer only one embryo to minimize a multiple pregnancy. This is because multiple pregnancies affect the health and safety of mum and baby.
- Success rates can be reported for different starting points. Per cycle started includes the 8% of cycles that are cancelled after starting the hormone drugs but before the egg retrieval (OPU) due to complications. Per egg retrieval includes all the women who get to this stage and either have an embryo transfer (with or without freezing) or fail to have one due to either no eggs retrieved, failed fertilization, failed embryo development etc. So results that only report per embryo transfer do not include all the women who have failed to get to this point.
- Freeze-only cycles are becoming increasingly common to protect both the woman and the embryos if the conditions are not optimal for the embryos to create a pregnancy (e.g. OHSS and abnormal hormone profiles). This means that the number of cycles having fresh embryo transfer in Australasia is declining, because they have been converted to a frozen embryo transfer cycle.
- Frozen embryo transfer cycles have the same if not higher chance of pregnancy than in fresh transfer cycles. This is mainly because the woman has not taken the ovary stimulating hormones which are known to reduce how receptive the uterus is to implanting embryos.
- Cumulative livebirth rates refer to the combined chance of getting pregnant from each IVF cycle that results in a fresh transfer plus the subsequent frozen embryo transfer cycles (one or more). Some clinics will present results that state your chance of getting pregnant is for e.g. 70% after two treatment cycles, which will include the frozen embryo transfer cycles that result from those two stimulated IVF treatment cycles.
Essentially, livebirth is the most meaningful outcome, because not all clinical pregnancies (heartbeat seen at 7 weeks) will result in the birth of a baby.
4. How lifestyle factors can affect success
The chances of success in each treatment cycle, is very much dependent on the client’s own set of personal characteristics such as cause of subfertility, reproductive history, lifestyle factors and most of all the woman’s age. However there is still a great deal that you can control regarding your lifestyle to better improve your chances. Click here to read further about improving your fertility fitness.
Clinics in New Zealand are all operating to the highest industry standards, so your choice of clinic will ultimately depend on the best fit and feel for you. Talk with your fertility doctor about your personal chances of success and taking home a healthy baby.