Male Fertility Following Spinal Cord Injury Update
Male fertility following spinal cord injury (SCI) remains a problem that many injured men deal with in their lives. After SCI, most men face obstacles when pursuing sexual activity and biologic fatherhood. Damage to the spinal cord contributes to sexual dysfunction and reduced semen quality. As a result, most men living with SCI experience erectile dysfunction, cannot ejaculate with sexual intercourse, and have poor semen quality. Sexual function can also be affected by low testosterone and premature symptoms of aging, which are both common after spinal cord injury.
With all of these challenges with male fertility following spinal cord injury, it seems like the deck is stacked against men with SCI who want to enjoy a healthy sex life or biologically conceive a child. Fortunately researchers studying male fertility following spinal cord injury in the lab of Dr. Nancy Brackett have been working hard for many years to understand the factors contributing to these issues and develop solutions for men living with SCI. They published a management algorithm for ejaculatory dysfunction that allows for semen retrieval, non-surgically, in 97% of men with SCI (Sinha et al., 2017).
The first step of evaluating the fertility potential of men with SCI involves obtaining a semen sample. Since very few men are able to ejaculate via masturbation or sexual intercourse, medical assistance is required to obtain sperm for assisted conception procedures. The choice of assisted conception depends largely on the number of healthy sperm that can be obtained from the man. Higher numbers of healthy sperm allow for the possibility of less invasive, less costly assisted conception procedures, such as intrauterine insemination, or even intravaginal insemination at home. Lower numbers of healthy sperm often require more expensive and invasive assisted conception procedures to achieve pregnancy, such as in vitro fertilization and intracytoplasmic sperm injection. A medical procedure called “penile vibratory stimulation” (PVS) usually results in the highest number of healthy sperm relative to other methods of semen retrieval in men with SCI who are unable to father children naturally.
A recent study (Chong et al., 2017) published by researchers in the lab of Dr. Brackett investigated three different methods of PVS in the same group of men with SCI to determine which one was optimal for achieving ejaculation. Clinical recommendations of attempting PVS with one device first are made based on the results. The findings of this study will help guide clinicians and patients toward the optimal method of PVS, and thereby, toward the optimal method of assisted conception.
After a sample is obtained, the next step is to evaluate the quality of the semen, which is often abnormal in men after spinal cord injury. Although sperm numbers are often normal, sperm motility (how well they move) is typically very low. This condition contributes to infertility. Previous research from Dr. Brackett’s lab has shown that inflammatory factors in the semen contribute to low sperm motility in men with SCI. They hypothesized that semen quality could be improved by a medication that interferes with the formation of some of these factors. The results of the study (Ibrahim et al., 2017), recently published in the Journal of Spinal Cord Medicine, showed that men with spinal cord injury had improved sperm motility after taking an oral medication (a pill) called probenecid for four weeks. This is the first study to report improved sperm motility after oral medication in men with SCI. Further research will determine the optimal dosage regimen. This treatment holds promise for improving reproductive options in men with spinal cord injury.
Articles – Varsha Sinha, Stacy Elliot, Emad Ibrahim, Charles M. Lynne, Nancy L. Brackett. (2017). Reproductive health of men with spinal cord injury. Topics in Spinal Cord Injury Rehabilitation 23(1):31-41
William Chong, Emad Ibrahim, Teodoro C. Aballa, Charles M. Lynne, Nancy L. Brackett. (2017). Comparison of three methods of penile vibratory stimulation for semen retrieval in men with spinal cord injury. Spinal Cord May 30 (epub) Emad Ibrahim, Teodoro C. Aballa, Charles M. Lynne, Nancy L. Brackett. (2017). Oral probenecid improves sperm motility in men with spinal cord injury. Journal of Spinal Cord Medicine May 2:1-4