Anyone contemplating assisted reproductive technology would be crazy not to ask this question. But, as you know, you can find supporting statistics for anything you want to do can’t you? Be warned: statistics in this field can be devilishly confusing.
Success rates in general
The very first in vitro fertilization of an human egg was achieved by Dr. Gregory Pincus in 1944. Ironically, he was the man who perfected the birth control pill as well. A team at Monash University in Melbourne produced the first IVF fertilization in 1973 but it did not survive to maturation. The Australians were piped at the post by the legendary British pair, Robert Edward and Patrick Steptoe. They performed a successful IVF for Lesley and John Brown which produced their daughter, Louise Joy, on 25 July 1978. It had taken 10 years and 467 attempts to produce the first live IVF birth. Since then, 4 million, 6 million or 8 million test-tube babies have survived—depending on your statistical source!
What is not disputed is the increasing success rate of what has become the mainstream treatment for fertility problems. In the 1980s it was 12% and by 2008 it was estimated at 35%. Presently the general success rate is sometimes as high as 60%.
The age factor
The mother’s age plays a major part in the success. Once again, published results vary wildly depending on the source.
Success rates in sample one: Women under 35 = 54.4%. Under 37 = 42%. Under 40 = 26.6%. Under 43 = 3.9%.
Success rates in sample two: Women under 29 = 27.7%. Under 34 = 24.9%. Under 39 = 17.1% Under 44 = 6.8%
The only reliable conclusion is that the success rates drop significantly for older women. This has been shown to be a factor. This echoes the case in normal conception. A healthy couple aged 20 to 30 have a 20% chance of normal conception per menstrual cycle. This drops to 10% as they near their 40’s. Current research reveals that a man’s age also affects the IVF outcome; “…a male partner under age 30 resulted in 70% incidence of live birth, compared to 54% for women the same age whose partner is 30-35.”
The egg factor
Choosing to use donor eggs rather than the intended mother’s eggs is another major factor in successful IVF, especially in older women. Some statistics show shown that a person over 40, using her own eggs, has a 7% chance of success. This rises to 50% and even higher when donor eggs are used.
Most people looking for IVF services will come at it after a long journey and several disappointments as it is a last resort in resolving fertility problems. Even if you simply want to be an only parent or part of the LBGTQ fraternity looking to enjoy parenthood, you will want to be sure the clinic you choose has the best possible success rate. This is vital and the trickiest part of all as there is no standardized statistical protocol and you can easily misunderstand the results they claim. Stay focused when assessing their claims: you want to know how many of the patients who walk through the door emerge with a healthy baby.
These are some mistakes you can make in assessing your chance of success:
- The results are for instances using the intended mother’s own eggs as well as those using donor eggs
- Successful pregnancy rates are not the same as live birth rates. Sometimes the “clinical” pregnancies are counted as part of the successes. A clinical pregnancy is still progressing at 20 weeks but does not necessarily come to term
- Success rates are calculated by cycles. i.e. live births divided by the number of egg retrievals
- Success rates are reported by the number of embryo implants, i.e. live births divided by the number of competent embryos implanted in the uterus
- Success rates are reported without reference to how many cycles were needed. Even women under 35 routinely undergo 3 cycles
The Society for Assisted Reproductive Technology (SART) has developed an online guide to help you make a personalised assessment of your realistic chances of having a successful IVF. There are so many variables to be considered: previous pregnancies, life style, general health issues and surrogacy that your chance of being successful is actually in your own hands. You can make your own success.