My wife and I just did IVF. We had 19 eggs and good-looking sperm -- but the next day only one fertilization. All sperm exposed to eggs were dead (non-motile), whereas the rest of the sperm (in the same incubator) were fine. The clinic has never seen anything like this -- have you? We don't know whether we're dealing with some rare syndrome or a lab error.

-- David

It is not infrequent that sperm do not fertilize the eggs or do not survive the incubation period. Laboratory error would not likely be present, as the same incubators and media are used in all cases. There are a number of factors that may play a role, but they probably are not that important as far as helping your physician determine the appropriate course to take now.

Sperm and egg are cultured in a nutrient media that requires a source of protein to promote sperm survival and fertilization. Some programs will utilize maternal blood serum to support fertilization and embryo growth. However, chemical factors in the mother's blood may be toxic to the embryos or sperm. Inherent abnormalities in the sperm may also affect sperm survival after processing for IVF.

But determining the cause of the poor sperm survival is not really necessary. Your physician will likely recommend a second attempt at IVF using sperm microinjection (ICSI). With this procedure, normal fertilization rates are usually achieved, and once the embryos divide, implantation rates are no different for ICSI-derived embryos than for those that occur by mixing sperm and eggs together in a small fertilization dish.