The clinical use of frozen semen banks.

In humans, use of frozen semen is still limited to the activities of a few centers. Procedure for freezing semen involves adding .1 ml of glycerol for each milliliter of semen to be frozen. The specimen is then transferred into sterilized ampules in 1 ml quantities and sealed. The ampules are then suspended in liquid nitrogen vapor at a temperature of -99 degrees C for 1/2 hour. Following this, ampules are maintained at -198 degrees C for storage, after appropriate coding. The major application is for donor inseminations. An experimental use is for pooling of a husband's specimens which are deficient in sperm numbers. Another clinical application is the storage of semen prior to sterility-inducing procedures in the husband, e.g., therapeutic irradiation. A similar application is for men contemplating vasectomy. Less than 1% of vasectomy patients have been interested in this procedure. There is no guarantee that the specimen will be usable at a later date. The longest successful utilization has been after 2 1/2 years. Results of insemination have been comparable with reports from elsewhere. Of a group of 92 pregnancies, 68 had delivered at term, 4 had spontaneous abortions, and 20 had not as yet delivered. Only 1 fetal abnormality was found, that of a child who had a missing digit. There were 1986 inseminations. Some required several inseminations. In this study, the total number of pregnancies through the use of frozen semen has been 137. The success rate is comparable to that obtained with nonfrozen specimens.