Sexual dysfunction including loss of erectile function of the penis, reduced ability to orgasm, and reduced sexual desire are more likely to occur among infertile men; ejaculation problems reduce the chances of conceiving.^10,13

In addition to the adverse effects of medicines and substances with pharmacological effects (see below), erectile dysfunction can result from health conditions. These include cardiovascular disease, diabetes, hormonal imbalances, neurological disorders, pelvic trauma or surgery, and anatomical abnormalities. Underlying physical causes account for 90% of erectile dysfunction, while purely psychological problems (‘performance anxiety’) is responsible for around 10% of cases.¹⁴

Retrograde ejaculation (RE), where semen flows backwards up the urethra into the bladder with little or no delivery of ejaculate, accounts for 0.3% to 2% of infertility cases. A loss of autonomic nerve control or physical changes mean the muscles at the bladder neck closure do not contract effectively at orgasm, making it easier for semen to flow into the bladder than be expelled out of the penis.^15,16

Possible RE causes include prostate or bladder surgery, radiation therapy in the pelvic area, diabetes, multiple sclerosis, nerve damage such as a spinal cord injury, and medication.^15,16