THE HYPOOSMOTIC SWELLING TEST IN RECURRENT MISCARRIAGE

Objective: To determine whether there is any association between sperm membrane integrity as determined by the hypo-osmotic swelling test sc ore and unexplained recurrent miscarriage. Design: Prospective observa tional study. Setting: Tertiary referral center for recurrent miscarri age. Patient(s): Semen samples from 20 male partners of women who had had three or more first trimester miscarriages of unexplained etiology and semen samples from 20 prospective semen donors of unknown fertili ty potential. Main Outcome Measure(s): Sperm density, sperm motility, sperm morphology, and hypoosmotic swelling test score. Result(s): Ther e was no difference in the median sperm density, the mean sperm motili ty, or the mean sperm morphology between the two groups. However, the recurrent miscarriage group bad a significantly lower hypo-osmotic swe lling test score than the control group. Conclusion(s): The hypo-osmot ic swelling test score is significantly lower in samples from men whos e partners have had unexplained recurrent spontaneous abortions. Viiit h the exception of cytogenetic abnormalities in peripheral blood karyo type, this is the first study to identify a male factor component ill recurrent miscarriage. (C) 1997 by American Society for Reproductive M edicine.