They can cause hydroceles as a surgical complications and are not known to cause hernia unless there is strain on the surgical site.
Hi
Thanks for writing to the forum!
If the varicocele is asymptomatic and infertility is not an issue, no treatment is required. Mild discomfort can be managed by wearing an athletic supporter or snug-fitting underwear during strenuous activity or exercise. However if the person wants to be a father in future, it is better to get it operated. Varicoceles are known to cause infertility as they affect sperm production. Usually it will not effect ejaculation unless complications arise. Also for a sports person, beyond a point it will be difficult to maintain a high activity level with symptomatic varicocele. Treatment options are surgical ligation, embolization and laparoscopic approach. Also you would need to maintain a diet rich in fibers and multivitamins and low on refined carbohydrates to bring strength to the surgical site and also to avoid constipation and straining. This will prevent recurrence too.
It is difficult to comment beyond this at this stage. Please let me know if there is any thing else and do keep me posted. Take care!