male infertility, sperm count, viagra, male fertility

Q: Does viagra affect sperm count? 

A: One study published in 2000 came to the following conclusion: "These results indicate that in normal subjects, acute sildenafil treatment does not modify semen characteristics and has a positive influence over the resumption of erections following ejaculation in the presence of a continuous erotic stimulus."

[From: Effects of sildenafil (Viagra) administration on seminal parameters and post-ejaculatory refractory time in normal males. Aversa A, Mazzilli F, Rossi T, Delfino M, Isidori AM, Fabbri A. Hum Reprod 2000 Jan;15(1):131-4]