People of childbearing age account for nearly 40% of potential renal transplant recipients in the U.S. Both men and women with chronic kidney disease (CKD) have significant fertility and hormonal deficits associated with uremia (excess urea and other nitrogenous wastes in your blood); chronic inflammation; and changes in reproductive hormone levels. 

Fertility issues in renal failure that uniquely affect men include:

• Hypogonadism (insufficient testosterone production) 
• Erectile dysfunction (ED)
• Oligoasthenozoospermia (combination of low sperm count and reduced sperm motility)

Kidney transplantation can improve these conditions to a degree, and research shows that the improvements are sufficient for at least some patients to father children either naturally or with assisted reproduction technology (ART).*

Causes of male infertility in renal failure

Several factors influence sub-fertility (delayed conception) and infertility in males with end-stage renal disease (ESRD), also called end-stage kidney disease (ESKD). 

• Testosterone has been shown to decrease in ESRD. This has been linked to pro-inflammatory markers, making chronic inflammation a potential contributing factor. 
• Uremia and long-term dialysis, particularly hemodialysis, have been associated with reduced testicular volume and sperm motility. 
• ED is related to the underlying causes of CKD (e.g., diabetes and hypertension) and direct effects of uremia, as well as:
  • Anxiety and depression 
  • Decreased activity
  • Poor body image associated with patients on dialysis
• Polypharmacy involving medications—such as beta blockers and diuretics, which are both known to hinder erections—is a likely contributor to the issue. These combined effects result in an over 50% prevalence of ED in male ESRD patients, even without the addition of changes in hormones and semen quality. 
• Many young male patients develop CKD secondary to congenital conditions such as autosomal dominant polycystic kidney disease (ADPKD), prune belly syndrome, and posterior urethral valves, which also predispose them to infertility. 

Benefits and risks of a kidney transplant

Increasing evidence suggests that a kidney transplant can improve male fertility before and during the window of fatherhood through raising hormone levels and reducing ED, though results are variable. Surgery carries mechanical risk, as well. The operation can potentially result in injury to the vas deferens, spermatic cord structures, and testicular blood supply. 

Transplants also appear to show less improvement in fertility for young recipients. The development of uremia during childhood or puberty seems to have significant, potentially irreversible effects on testicular health and semen quality even decades later. 

A recently published study followed 24 male patients with ESRD who underwent kidney transplantation at approximately 10 years old and compared them to healthy age-matched controls. 

Over 20 years, the study team noted:

• Threefold decrease in average testicular size 
• Lower testosterone level
• One hundred-fold decrease in sperm count 
• Azoospermia (absence of viable sperm in semen) in 28% of patients

Assisted reproduction therapy 

If patients are still unable to conceive naturally following transplant, they may benefit from ART, such as intracytoplasmic sperm injection (ICSI). Several studies have reported successful ICSI in a variety of male transplant recipient populations, suggesting that ART is a viable option for couples with male infertility following renal transplant, though with mixed success.

While reproductive outcomes seem to be less successful for pediatric and adolescent transplant recipients, many male transplant patients will likely be able to father healthy children, whether through natural conception or with the support of ART. 

*Lundy, S.D., & Vij, S.C. (2019, Apr.). Male Infertility in Renal Failure and Transplantation. Translational Andrology and Urology. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6503227/