Embryo development, pregnancy and twin delivery after microinjection of 'stump' spermatozoa

Intracytoplasmic sperm injection was performed with immotile spermatozoa af fected by tail 'stump' defect, and resulted in normal fertilization, embryo transfer and pregnancy in a 35-year-old female. The husband had a consangu ineous ancestry. Two healthy babies, a male and a female, were born and thi s confirms that male infertility due to certain genetic sperm defects can b e overcome by the intracytoplasmic sperm injection-assisted reproduction te chnique. The likely genetic origin of this sperm defect and the probability of the male offspring inheriting this sperm defect should be considered. T he fertilization ability of stump spermatozoa, microinjected into the oocyt e, is explained on the basis of experience from our previous research.