Phimosis is a condition where the foreskin cannot be retracted over the glans. It is due to a tight prepucial opening which may be congenital or secondary to infection. Recurrent infection of the prepuce (posthitis) causes scarring and narrowing of the prepucial opening.
At birth physiological phimosis is present due to adhesions between the glans and inner prepuce. This is primary phimosis and it usually clears in the first few years of childhood. Forceful retraction of prepuce during these years is not recommended as it may leads to scarring and secondary phimosis.
Phimosis is left untreated can cause penile cancer, urinary tract infections and balanitis.