High fertilization rate obtained after intracytoplasmic sperm injection with 100% nonmotile spermatozoa selected by using a simple modified hypo-osmotic swelling test.

OBJECTIVE

To report a high fertilization rate after intracytoplasmic sperm injection (ICSI) in patients with 100% nonmotile spermatozoa selected by a simple modified hypo-osmotic swelling test.

DESIGN

Clinical study.

SETTING

Hospital-based IVF center.

PATIENT(S): Three couples with infertility due to asthenospermia.

INTERVENTION(S): The hypo-osmotic swelling test with 150-mOsm NaCl solution was used to select viable spermatozoa before ICSI. Three patients provided semen samples and one of these three also had a testicular biopsy.

MAIN OUTCOME MEASURE(S): Selection of viable spermatozoa using the hypo-osmotic swelling test with 150-mOsm NaCl solution for ICSI.

RESULT(S): No motile spermatozoa were found in three ejaculated semen samples and one testicular biopsy. Fifty-seven metaphase-II oocytes were injected with hypo-osmotic swelling test-positive ejaculated or testicular spermatozoa. Fifty-five (96.5%) of these oocytes were intact after injection. Forty-two (76.4%) of 55 oocytes showed two pronuclei, and 40 of the 42 fertilized oocytes cleaved. One patient had all embryos cryopreserved because of the risk of hyperstimulation; two other patients had embryos transferred. One ongoing pregnancy resulted.

CONCLUSION

This hypo-osmotic swelling test with 150-mOsm NaCl solution is a simple and efficient method for selection of viable spermatozoa. A high fertilization rate can be obtained using ICSI with viable spermatozoa selected by using this hypo-osmotic swelling test.