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Updated: May 21, 2026

Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI
Published on: April 18, 2011
Semen quality in ejaculates produced by masturbation in men with spinal cord injury
A S Q Kathiresan1, E Ibrahim, R Modh
1Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Miami, Miller School of Medicine, Miami, FL, USA. anu.kathiresan@gmail.com
Study Design:
Retrospective study.
Objectives:
Most men with spinal cord injury are anejaculatory. Much has been reported about their semen quality collected by penile vibratory stimulation and electroejaculation (EEJ). What is not well-described is the nature of semen quality in SCI patients who can ejaculate by masturbation. This study was performed to understand the degree to which their semen quality differed from that of anejaculatory SCI patients versus that of healthy non-SCI control subjects.
Setting:
University of Miami.
Methods:
Retrospective chart review of Male Fertility Research Program participants from 1991 to 2011.
Results:
Of 528 SCI subjects, 444 met inclusion criteria of completing an algorithm in which ejaculation occurred by masturbation (n=43), PVS (n=243), or EEJ (n=158). Sperm motility was higher in the SCI-masturbation group (36.9%) than the PVS group (25.9%, P<0.001) or EEJ group (15.0%, P<0.001), but lower compared with a control group of 61 non-SCI healthy men who collected their semen by masturbation (58.0%, P<0.001). The SCI-masturbation group had similar antegrade sperm concentration (83.3×10(6) cc(-1)) as the PVS group (77.4×10(6) cc(-1)) and control group (82.0×10(6) cc(-1)), but higher than the EEJ group (49.8×10(6) cc(-1), P<0.001). The SCI-masturbation group had significantly more men with incomplete injuries (84%) than the PVS group (54%, P<0.01) or EEJ group (41%, P<0.001).
Conclusion:
This is the first report focusing on semen quality obtained by masturbation in men with SCI. Sperm motility was higher in men with SCI who could, versus could not, ejaculate by masturbation. Completeness of injury may contribute to this difference.
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