The question arises: how many eggs are good for IVF? This answer depends on the individual woman undergoing the egg retrieval, so it would not be valid to give an average. But if you want to know specifics, I can tell you that on average a woman who is ovulating normally should get at least two eggs per retrieval. So let’s use this as our low-end estimate—some doctors wouldn't even count it as a valid egg retrieval (though some would).
Some young women with a robust egg reserve, or those who have polycystic ovary syndrome, can have more than 40 eggs retrieved at one time. There is plenty of variation within this 2-40 range, mostly due to the woman’s age having the egg retrieval.
How many eggs retrieved IVF?
So how many eggs are retrieved in IVF? It depends on a woman's age, as younger women tend to have better-quality eggs. Therefore, an older woman will need more retrieved eggs to become pregnant than a younger one will with the same chance of success.
How many eggs retrieved IVF? In general, however, a woman who has about 10 to 12 mature eggs after egg retrieval will have a good chance of having at least one normal embryo—giving her about 65 percent odds of getting pregnant (not every egg retrieved will be viable enough to fertilize)
The above figure is 65, because not all embryos that appear normal will be able to develop into pregnancies. In order to increase the chances of a successful implantation, multiple high-quality embryos should be available for transfer in case the first one does not take hold. According to RMA research, women with three normal embryos have an 95 percent chance of getting pregnant.
If a woman wants to have two children, she will likely need more than 12 mature eggs because most of them produce genetically normal embryos. For simplicity's sake, if 12 mature eggs are usually enough for one normal embryo—which has a 65 percent chance of leading to a pregnancy—24 would be ideal for someone who wants two children.
You should also keep in mind that pregnancy rates will be affected by the overall quality of your eggs. Every woman, no matter her age, has normal and abnormal eggs. So every ‘batch’ of eggs recruited during an IVF cycle will vary in its genetic makeup—and the yield from each such cycle will thus vary as well: some batches resulting in more normal embryos than others. We are often asked the question: how many eggs needed for ivf?
How many eggs for IVF: Does the amount matter?
We can help answer this question: how many eggs are good for IVFf? Most fertility doctors agree that the more eggs you have retrieved, the higher your chances of success – in other words, pregnancy and live birth. Although some research shows that egg retrieval is more successful when a very high number of eggs are retrieved (in the mid- to high 20s and beyond) in one cycle, most traditional IVF doctors still prefer retrieving fewer eggs (in minimal stimulation IVF, or mini-stim IVF, doctors are less concerned with the number of eggs).
For example, 7 eggs retrieved is better than 3 eggs retrieved; 10 eggs retrieved is better than 7; and 13 egg retrievals are the best of all in terms of projecting a good outcome for IVF success.
Why is getting more eggs better than having just a few? As we mentioned above, not all eggs are genetically normal and thus will not lead to genetically normal embryos. The more eggs you have to fertilize, the higher your chance of having one or two normal embryos. This process relates to IVF attrition.
How many eggs is good for IVF: What is IVF attrition?
Attrition is a natural part of the IVF process, in which your chances of getting pregnant decline as time goes by. For every step of the IVF process (and there are many!), there is a chance that something could go wrong—making it a numbers game. The higher your egg number at the beginning means you're more likely to obtain one normal embryo; this will lead, in turn, to a healthy pregnancy and live birth once all steps are done.
So what are the steps?
First is the egg retrieval – a poor response to ovarian stimulation or the presence of a condition like polycystic ovary syndrome can cause your doctor to retrieve fewer mature eggs than anticipated. For example, if he retrieves 15 mature eggs but 19 were expected—the loss of four immature ones is attributable to these factors.
Next is fertilization – in an average woman's ovaries, about 80 percent of eggs are viable. So if you have 15 mature eggs, let’s say only 12 will actually fertilize—the remaining three never make it that far.
Next is blastulation – how many fertilized eggs, now called embryos, will reach the all-important blastocyst stage and be eligible for Preimplantation Genetic Testing (PGT) for Aneuploidy, which gives doctors a good idea of each embryo's chances of becoming a successful pregnancy? About 30-50 percent of embryos will reach this stage, so we can now consider ourselves lucky to have found two.
Now comes the PGT-A testing – most women over 40 years old don’t make eggs that can create a baby. Every single one of the six embryos you created would not develop into a healthy baby. As time passes, the chance of obtaining a baby from eggs that have not completed the initial stage of DNA production diminishes. Eggs cannot restart that procedure as time passes. It might mean that three of the six embryos will not be viable.
Since miscarriage does not usually happen to women that have abnormal embryos, and because only healthy embryos are transferred, a woman with an implanted embryo may not conceive on the first attempt. If a woman has three healthy embryos, the chances that she will conceive are 95 percent.
We hope we were able to help you understand IVF: how many eggs is good?