ICSI vs. Natural Fertilization

What are the pros and cons of using ICSI vs. natural fertilization?

Hi Tiny Dancer,

I dedicated a blog post to your question Sperm Injection: the Good, the Bad and the Ugly http://fertilitylabinsider.com/2010/...-and-the-ugly/. The short answer is that ICSI is an amazing advance for men that have very few sperm or have sperm that can't swim because it gives them the only chance to conceive. Having said that, some programs use ICSI on nearly 100% of cases to insure that they have no cases of failure to fertilize which could then be attributed to not having done ICSI. But ICSI is not a guarantee of fertilization because just putting the sperm inside the egg is not fertilization. The egg must respond to the sperm, commingle DNA and so on. There are quite a few steps post sperm insertion into egg. Also, when ICSI is used, there is no "natural selection". The tech simply selects a decent looking sperm and injects. Nature would have the sperm compete and the fastest strongest swimmer would theoretically get to the egg first. When the first sperm enters the egg, the egg chemically slams the door shut so no more sperm can penetrate. There are other considerations for some patients that I talk about in the blog post but you get the idea. It has it's uses but may have drawbacks too. There are some studies that suggest that babies from ICSI'd eggs have a slight statistical increased incidence of some genetic problems, but it's not clear whether that is due to the procedure or the patient population that needs the procedure. So use it if you need it, but you should ask your doctor what his/her reasons are for ordering ICSI. Hope this helps. :) Carole

Thanks Carole for the information. My DH's sperm analysis came back fine but because I am 37 and may not have many eggs (who knows how I will react to the Stims, I had an astral follicle count of 15 on my day 3 testing), I want the best odds for highest fertilization. My clinic uses ICSI the majority of the time but there is still an option of natural fertilization as well. What would you do if you were me?

Hi Tiny Dancer,
In your case, I would probably do ICSI because you said you "want the best odds for fertilization". Ensuring that a sperm enters every mature egg removes that variable (sperm penetration of the egg) from the possibility of fertilization failure. Since the lab does ICSI a lot, technical proficiency is probably not a concern and it is always good to go with a lab's strengths. My previous blog post (link above) explains some of the cautions associated with ICSI but your case may not be particularly affected by any of those concerns. Please remember that my opinion is just an opinion. In the end, it is ultimately your decision, not mine, because I will not be living with the consequences either way. A crystal ball would be just the thing to help us with these decisions. :) Best wishes,
Carole