Clinical and Consumer Trial Performance of a Sensitive Immunodiagnostic Home Test That Qualitatively Detects Low Concentrations of Sperm Following Vasectomy
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Purpose:
Compliance with post-vasectomy semen analysis could be improved with the availability of a simple, rapid and accurate home test. SpermCheck Vasectomy®, a highly sensitive lateral flow immunochromatographic diagnostic device, was designed to detect extreme oligospermia or azoospermia in men after vasectomy. We report the results of clinical and consumer testing of SpermCheck.
Materials and Methods:
A prospective, noncomparative observational study assessed the ability of SpermCheck Vasectomy to predict post-vasectomy sperm counts obtained using a hemacytometer procedure based on standard World Health Organization methodology. Consumer studies evaluated ease of use.
Results:
A cohort of 144 post-vasectomy semen samples was tested in the clinical trial. SpermCheck was 96% accurate in predicting whether sperm counts were greater or less than a threshold of 250,000 sperm per ml, a level associated with little or no risk of pregnancy. Sensitivity was 93% (95% CI 79% to 98%) and specificity was 97% (91% to 99%). The positive predictive value of the test was 93% (79% to 98%), and most importantly the negative predictive value was 97% (91% to 99%). The test gave a positive result 100% of the time at sperm concentrations of 385,000/ml or greater. Consumer studies with 109 lay volunteers showed that SpermCheck was easy to use. Volunteers obtained the correct or expected test result in every case and the correct response rate on a 20 question survey about the test was 97%.
Conclusions:
SpermCheck Vasectomy, a simple and reliable immunodiagnostic test that can provide evidence of vasectomy success or failure, offers a useful alternative to improve compliance with post-vasectomy sperm monitoring. It is currently the only Food and Drug Administration approved test for this purpose.
References
- 1 : General and anomalous sperm disappearance characteristics found in a large vasectomy series. Fertil Steril1989; 51: 859. Google Scholar
- 2 : A prospective study of time and number of ejaculations to azoospermia after vasectomy by ligation and excision. J Urol2003; 170: 892. Link, Google Scholar
- 3 : Postvasectomy semen analysis: are men following up?. J Am Board Fam Pract2005; 18: 44. Google Scholar
- 4 : Patient noncompliance after vasectomy. Fertil Steril1997; 68: 552. Google Scholar
- 5 : The high rate of noncompliance for post-vasectomy semen examination: medical and legal considerations. J Urol1990; 144: 284. Link, Google Scholar
- 6 : Postvasectomy semen analysis: why patients don't follow-up. J Am Board Fam Pract1991; 4: 5. Google Scholar
- 7 : Progress in developing an immunochromatographic device for sperm detection. Clin Immunol Newsl1999; 19: 52. Google Scholar
- 8 : Tissue specificity of the acrosomal protein SP-10: a contraceptive vaccine candidate molecule. Biol Reprod1994; 50: 615. Google Scholar
- 9 : Purification and microsequencing of the intra-acrosomal protein SP-10: Evidence that SP-10 heterogeneity results from endoproteolytic processes. Biol Reprod1992; 47: 11. Google Scholar
- 10 : Biochemical and morphological characterization of the intra-acrosomal antigen SP-10 from human sperm. Biol Reprod1990; 42: 181. Google Scholar
- 11 : Assay for recombinant and native human intraacrosomal antigen SP-10. Am J Reprod Immunol1993; 29: 231. Google Scholar
- 12 : Fatherhood without apparent spermatozoa after vasectomy. Lancet1994; 344: 30. Google Scholar
- 13 : Oligozoospermia: recent prognosis and the outcome of 73 pregnancies in oligozoospermic couples. Andrologia2006; 38: 87. Google Scholar
- 14 : Contraceptive efficacy of a depot progestin and androgen combination in men. J Clin Endocrinol Metab2003; 88: 4659. Google Scholar
- 15 : A multicenter contraceptive efficacy study of injectable testosterone undecanoate in healthy Chinese men. J Clin Endocrinol Metab2003; 88: 562. Google Scholar
- 16 Contraceptive efficacy of testosterone-induced azoospermia in normal men: World Health Organization Task Force on methods for the regulation of male fertility. Lancet1990; 336: 955. Google Scholar
- 17 Contraceptive efficacy of testosterone-induced azoospermia and oligozoospermia in normal men. Fertil Steril1996; 65: 821. Google Scholar
- 18 : 10th Summit Meeting consensus: recommendations for regulatory approval for hormonal male contraception. October 22-23, 2006 Contraception2007; 75: 166. Google Scholar
- 19 : Persistence or reappearance of nonmotile sperm after vasectomy: does it have clinical consequences?. Fertil Steril1997; 67: 332. Google Scholar
- 20 : WHO Laboratory Manual for the Examination of Human Semen and Sperm-Cervical Mucus Interaction. Cambridge: Cambridge University Press1999. chapt 2, pp 14-17 and chapt 4, p 37. Google Scholar
- 21 Sperm concentration. In: Manual on Basic Semen Analysis. Nordic Association for Andrology and European Society for Human Reproduction and Embryology 2002; chapt 4, pp 7-13. Available at www.andrology.dk/manual2002.pdf. Google Scholar
- 22 : Two-sided confidence intervals for the single proportion: comparison of seven methods. Stat Med1998; 17: 857. Google Scholar
