Understanding IVF success rates

Written by Assoc. Prof. Peter Illingworth
06 Nov

If you’re starting IVF treatment or considering getting a second opinion, most patients will take a keen interest in a clinic’s IVF success rates. But what do these figures really mean and how do you compare them between clinics? 

Defining IVF success

The first thing to be aware of is that unfortunately, there is no standard definition for reporting ‘success’ when it comes to IVF. One approach is to report clinical pregnancy rates (a pregnancy confirmed by a blood test and ultrasound scan, usually at around 6-8 weeks).  However, it is important to remember that, as a result of miscarriages, not all clinical pregnancies will lead to live babies and clearly it’s the likelihood of welcoming a newborn baby into their family that is important.  However, as the birth takes place in the year after the cycle, the clinical pregnancy rate provides the most up to date statistic.

What is an IVF 'cycle'?

When a woman begins IVF she normally goes through a series of injections leading to an egg collection followed by transfer of an embryo.  Sometimes the cycle is cancelled before the eggs are collected, in which case, the normal charges of IVF do not apply.  Sometimes after the eggs have been successfully collected there may be no transfer because no embryos have developed.  In other cases, your doctor may advise you to postpone the transfer for instance, to carry out genetic testing on your embryos or to prevent complications if your hormone levels are very high.  In other cases, many embryo transfers can result from one egg collection.  Different clinics use different sub-groups to describe their results.  At IVFAustralia, we describe our success rates per each embryo transfer as this is a constant event that is easy to compare.  However you do need to be aware that, in some cases, you may not even have an embryo transfer.  In other cases, one egg collection can result in several embryo transfers to give you, overall, a higher chance of success from the egg collection.

Who is in the ‘successful’ group?

When comparing fertility clinics, this is generally when you realise that you’re often not comparing apples with apples.

The most important factor affecting the chance of pregnancy success, whether spontaneous or via IVF, is the age of the woman.  A woman’s fertility starts to decline slowly from her early 30’s onwards but declines rapidly after the age of 40.  It’s not too surprising then that the average age of a woman undergoing a fresh IVF cycle is 36*.  Look for a clinic that is transparent with its success rates and breaks them down into age bands.  If you’re 40 you simply cannot compare your chance of success with a 30 year old.

Here’s an example of IVF Australia’s Success Rates, which shows the variation between age bands:

IVF Success Rate

The other differences to look for are whether the success rates are based on all women starting an IVF cycle or only those that have an embryo to transfer, whether the rates include frozen embryo transfers, or whether their sample includes women using donor eggs.

Single embryo transfer

Australian fertility specialists have led the world in reducing the number of embryos transferred in an IVF treatment cycle – this reduces the chance of multiple pregnancies and therefore the risks to mothers and babies. At IVFAustralia 82% of all patients undergoing IVF treatment have a single embryo transfer, compared with 76.3% of the national cycles, and the chance of having a multiple birth through treatment at IVFAustralia is only 5.3% which is significantly lower than the national average of 6.5%.

It’s all in the numbers

As with all statistics, the higher the sample the more robust and reliable the figure. Larger clinic groups involving many fertility specialists caring for patients can offer you this, whereas individual clinics have a smaller patient population to draw from.

Also bear in mind that many clinics report cumulative rates, on average you will require more than one cycle before you are successful. Be aware of what you are trying to compare.

Is there an authoritative source of IVF success rates in Australia?

The University of NSW collates the success rates of all IVF cycles in Australia in an annual report. The most recent data available is for 2012 and includes pregnancy and live birth rates by a woman’s age, treatment type and the cause of infertility.

The latest average figures for all of Australia show that 22.8% of fresh IVF cycles result in a live birth and 22.2% of frozen/thawed embryo transfer cycles resulted in a live birth. Birth rates were much higher for younger women. Among those aged 30–34, the birth rate was 32.3% for fresh cycles and 26.4% for frozen/thaw cycles. For women aged 45 or over, it was less than 1.6% and around 5.4% respectively.* These figures are a good benchmark for you to compare any clinic success rates to. Be wary of any clinics that misrepresent this average in order to present a more dramatic looking result.

Can technology improve the likelihood of IVF success?

A number of technological interventions have been found to improve IVF success rates such as pre-implantation genetic diagnosis (PGD) to avoid chromosomal abnormalities, and, in some cases of male factor infertility,digital high magnification imaging of sperm. Other key advancements have been around fertilisation, embryo development and freezing methods. In addition, there are some emerging trial techniques (such as uterus scratching for repeat implantation failure) that are showing considerable promise.

Another example of this is the developments in cryopreservation techniques where the success rates after frozen embryo transfer are now equivalent to fresh cycle transfers, which ultimately reduces the number of cycles patients need to undertake to achieve a baby.

Make it about you

Whether you are embarking on fertility treatment for the first time, or seeking a second opinion after previous unsuccessful cycles, the best way to understand the likelihood of success for you and your partner is to have a consultation with a fertility specialist. Our role is to give you a thorough understanding of where you are now, and to work with you to develop the most suitable treatment plan moving forward.

Remember bar graphs are not always what’s important – achieving a pregnancy and delivering a baby is the definition of success. You need to find a fertility specialist you are comfortable with and who is caring for you, constantly refining your treatment to maximise the chance of success.  This may also include referring to an expert review of experienced colleagues for challenging cases and bringing the latest technology to bear where necessary.

Read more: IVF Success Rates for Greater Sydney, IVF Success Rates for Melbourne, IVF Success Rates for Qld

* Assisted reproductive technology in Australia and New Zealand 2012, National Perinatal Epidemiology and Statistics Unit, UNSW Australia 



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Related Articles

Conceiving in your 40s, what are the chances?

I was recently asked to comment in a Sun Herald article on 26th August (also published online here: Sydney Morning Herald) on Collette Dinnigan, who pregnant at the age of 46, has called on women not to leave it too long to try for a baby.

It is always news when a high profile personality such as Ms Dinnigan, has a child, particularly when the personality in question is a bit older.  The difficulty is that these occasions, while very happy for the people involved, give a misleading picture of the actual likelihood of conception in these circumstances.  Remember that high profile personalities such as Ms Dinnigan, are human beings who quite rightly value their privacy and so very rarely (quite understandably) talk to the press when things aren’t going so well.  It was therefore, a particularly courageous action of Ms Dinnigan, while celebrating her own happiness, to so publicly, point out the difficulties that may face other women, seeking the same fulfilment.

What then, are the issues for women in their forties who are planning to have a child?

The main difficulty is that conceiving is simply harder at that age and, even once a woman does conceive, the risk of miscarriage is higher.  Surprisingly, although we have very good data about the effects of age on IVF conception (more shortly), we don’t have very good statistics about the effects of age on conceiving naturally. The limited available data about natural conception comes from old population studies or studies of unique populations, such as the Hutterites of North America, who do not use contraception.  Interestingly these data, such as they are, seem to be entirely consistent with the more modern and abundant IVF data.  Generally, in one year of trying, 75% of women under 30 years and 66% of 35-year-old women but only 44% of 40-year-old women will achieve a live baby naturally.

The main explanation for this, is that women are born with a finite number of eggs, and from that moment onwards, the number of eggs is declining all the time, until women go through their menopause at around 50-51.  Nonetheless, women in their 40s do still ovulate each month.  What is it about their eggs that cause all these problems?

A common misunderstanding with some women is that the fact she looks and feels young, and leads a healthy lifestyle, means that her eggs will be healthier. I regularly see women who have taken enormous care with their fitness and their health.  The rest of their body is in great shape, completely fit and ready to carry that longed-for pregnancy.  Sadly, despite this, the eggs still can’t do it.  The effects of time are remorseless and, sadly, there is no wonder drug to fix it.

Scientists have shown that eggs from older women are more likely to have an abnormal makeup making pregnancy less likely, miscarriage more common and increasing the risk of Down Syndrome, a condition where a child is born with an extra chromosome number 21.

Nor is IVF a cure for this problem. For women, in their early 40s, IVF is still a good thing to try and gives significantly higher success rates than trying naturally.    However, IVF success rates fall sharply after the age of 40 and by the time a woman is 45 are close to zero.

So, what’s the good news?  Well despite all of the above, many women do conceive in their forties, either by IVF, or naturally, and have very happy healthy families.  It is obviously better to have your family earlier, if you can, but all hope is not lost, just because you’re past 40.  Conception and early miscarriage are the big problems but, if you do conceive and get past the first few weeks, by far the most likely outcome will be a healthy child.  While the risk of Down Syndrome is increased, most of the other problems that affect young children are not increased by being conceived a later maternal age.

Finally, many women worry that by having their children later, their long term health and emotional development may be affected.  On the contrary, we now know that the children of older mums grow up to be as healthy and bright as any other child.

Assoc. Prof. Peter Illingworth
06 Nov

Snapshot of Fertility in Australia

There have been a number of happy and high profile stories in the press recently about older celebrities giving birth to healthy children. Stories like this used to be extraordinary, but they certainly seem to be on the increase. While this trend is supported by data that shows the fertility rate and numbers of births are increasing for women over 30 and especially for women in their early 40s, women and couples should understand the risks associated with having children later in life.  IVF Australia, Melbourne IVF and Queensland Fertility Group, have teamed up to create their latest infographic - “Fertility and Age in Australia” which explores some of these issues.
 Fertility in Australia infographic

Assoc. Prof. Peter Illingworth
06 Nov

Paternity, Maternity, Equality

Conceiving a baby in a same sex relationship

IVFAustralia, and its partner clinics Melbourne IVF, Queensland Fertility Group and TasIVF, are proud supporters of ‘rainbow families’. IVFAustralia were an Official Supporter of Sydney’s Gay and Lesbian Mardi Gras this year, and we’ve seen the number of same sex couples accessing our donor program double in the last year.
In 2011, a survey of 3,835 LGBT people found 33% of women and 11% of men had children1 - but close to 40% reported wanting to have children or have more children. This so-called ‘gayby’ boom is thanks to changes in community attitudes and laws, including better access to Assisted Reproductive Treatments for lesbian and single women.
So, if you’re hoping to experience the joy of starting a family within a gay or lesbian relationship, what do you need to consider?

How long will it take to conceive?

Generally speaking, we’d expect a healthy woman with no fertility issues to fall pregnant through IVF or Artificial Insemination within six months. You can prepare for pregnancy by improving your diet, doing regular exercise and other lifestyle factors.
When you access the donor program there are a few extra decisions you need to make.
Do you choose a known donor, or an anonymous donor? In a lesbian relationship, do you want to implant an embryo with eggs from one mother into the other? Should you store some sperm from the same donor for later, in case you’d like a related sibling? For two dads, the process of finding a surrogate can also be complex.

How do we choose a donor?

Our fertility clinics offer access to both Australian and US* donor sperm. The access fee for US donor sperm is higher, but the waiting list is also shorter as there is a shortage of local donors (gay men, we’d love to hear from you!)
When you’re using donor sperm or eggs, there are a few legal, emotional and ethical factors to consider and a counsellor will help you work through these concerns so you can make the best decisions for your family’s future.

Are there any legal issues?

Each state has different laws about parental recognition and access, so it’s worth seeking specialist advice before you start.
For example, in Victoria, the Victorian Assisted Reproductive Treatment Act (2008) removed discrimination against lesbian and single women with regard to fertility treatment, recognised parenting status for non-birth mothers and also effectively legalised ‘altruistic’ surrogacy. It also recognises lesbian couples as equal parents of their child or children as long as they were in a de facto relationship.

What else should we be prepared for?

30 years of research2 has shown that the children of same-sex parented families do just as well as the children of heterosexual parents socially, educationally, physically and emotionally.

The issues your children will face as they get older are just the same as the issues facing any children conceived using donor sperm or eggs: Where did I come from? Should I contact my donor? You need to be prepared for these questions at some point.
In the meantime, we hope we can help you fulfil your dream of having a baby, and that you will experience the joys of pregnancy, birth and parenthood.

What should be my next steps?

If you would like to learn more about the fertility treatments available for same-sex couples in your regions, visit one of our websites. 

 * IVFAustralia and Queensland Fertility Group patients only.

1 Leonard et al. (2012) Private Lives 2: The Second National Survey of the Health and Wellbeing of GLBT Australians, The Australian Research Centre in Sex, Health and Society, Melbourne
2Rainbow Families Council of Victoria (2010) Rainbow Families and the Law, RFC, Melbourne, http://www.rainbowfamilies.org 

Assoc. Prof. Peter Illingworth
06 Nov

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