Many women think that IVF– the most complicated, monitored, and precise treatment for infertility will ensure success – a “take-home baby”. Success, however, depends upon many factors. Fertility doctor Jane Miller explains to her patients that the woman’s age is the most important factor.
The impact of advancing female age on IVF success is sobering. A woman’s age is, unfortunately, also the age of her eggs. Nothing she has done (or is doing) i.e. having taken birth control pills, taking vitamins, exercising moderately, or eating a balanced, healthy diet will lessen the impact of age. In a sense, a woman’s eggs have a shelf – life ….like in the supermarket.
National average data on IVF Success (taking home a baby – per cycle – with a woman’s own eggs) are 40% in the late 20s. The percentages start to drop after 30 and the drop is more linear after 35. By 38, national average success is 30% take-home baby per cycle. By age 45 IVF success with one’s own eggs is 1%.
Although success does vary with the number of embryos transferred transferring more than one at a time does not significantly increase the chance of a live birth. It does, however, increase the chance of a multiple gestation which has many risks of its own.
So how do we know if someone has any “good” eggs? There is no test for egg quality. Even in the IVF laboratory we can’t look at an egg and tell if it is normal. We have to inseminate it with sperm, culture it for 5 days, and then assess the resulting embryo’s grade (what it looks like) and genetics.
We can, however, assess a woman’s ovarian reserve which will give us an idea of how many eggs we can hope to retrieve. In general, the more eggs we can retrieve, the more chances there are to have a normal embryo that can develop into a baby. It is, to an extent, a “numbers game”.
What then can we expect?
- IVF success rates drop in the thirties and faster in the mid-thirties and beyond
- Egg age is very important
- IVF success rates do not drop if young donor eggs are used
- The age of the uterus has little impact on the chances for success