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Within a certain range, early cleavage is a good sign. If it is very rapid (i.e. way ahead of the natural division cycle), it is a sign of abnormality, as is slow division.
All things being equal, success (term pregnancy) with testicular/epididymal sperm is significantly lower than with ejaculated sperm. It is related to the packaging of the DNA inside the sperm head. Testicular, and to some extent epididymal, sperm have not completed the "packaging" process so when it comes time to unwind inside the egg things go wrong. As you pointed out, the detrimental effect of this abnormality does not manifest until after Day 3. In TESA/PESA cases, significantly fewer embryos make it to the blastocyst stage, or, if the do, the developmental potential of the blastocyst is lower. Hence the hurry to put them back in on Day 3 rather than risk nothing to transfer in Day 5.
A healthy life style may improve your chances of implantation IF an embryo reaches the blastocyst stage, but a healthy lifestyle will not affect the quality of your eggs in a genetic sense. Unfortunately, you can't repair a genetically abnormal egg (or sperm for that matter) by excercising frequenty and eating right. There is nothing you or your husband can do to improve the developmental potential of the embryos. Tweaking stimulation protocols can sometimes help a little by getting more mature eggs at retrieval, but in the end its simply a numbers game. The more eggs that fertilize, the better the chance of getting a good egg with a good sperm.
Choosing the "best" sperm will contribute to the success of ICSI. However, when working with testicular sperm, they all look bad and picking a "good" one is virtualy impossible. It is a little easier with epididymal sperm, but not much. There is some variation in the skill level of embryologists working in an IVF lab. However, due to the difficulting of TESA cases, they are almost invariably performed by the most experienced and senior embryologist(s). I don't think you have to worry there.
There have been some reports lately that cryopreservation of sperm can induce genetic damage. I don't know how much stock I put in these reports. Frozen-thawed sperm has been used safely in ART procedures for more than 20 years and this is the first time anyone has suggested there may be a genetic problem with the sperm. It also doesn't make a whole lot of biological sense becase, in mature sperm, the DNA is very tightly packed inside the sperm head and, because of this, most chemical substances cannot penetrate the nucleus to alter the DNA. If you believe their report, then testicular sperm may be suseptable to cryodamage becasue the packaging process may be incomlete. I always prefer working with fresh testicular sperm on the day of egg retieval because there's more to choose from to get the "good" sperm. Frozen-thawed is more convient for the lab, but I think fresh is better (my opinion only - not based on scientific evidence).
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