▁pressure ▁r ises ▁and ▁breath ing ▁becomes ▁quick er . ▁The ▁increase ▁in ▁blood ▁flow ▁in ▁the ▁gen ital ▁and ▁other ▁regions ▁may ▁lead ▁to ▁a ▁sex ▁flush ▁sometimes , ▁in ▁some ▁men . ▁ ▁As ▁sexual ▁stim ulation ▁continues , ▁org asm ▁begins , ▁when ▁the ▁mus cles ▁of ▁the ▁pel vic ▁floor , ▁the ▁vas ▁de fer ens ▁( between ▁the ▁test icles ▁and ▁the ▁pro state ), ▁the ▁sem inal ▁ves icles ▁and ▁the ▁pro state ▁g land ▁itself ▁may ▁begin ▁to ▁contract ▁in ▁a ▁way ▁that ▁forces ▁s perm ▁and ▁sem en ▁into ▁the ▁u re th ra ▁inside ▁the ▁pen is . ▁Once ▁this ▁has ▁started , ▁it ▁is ▁likely ▁that ▁the ▁man ▁will ▁continue ▁to ▁ej ac ulate ▁and ▁org asm ▁fully , ▁with ▁or ▁without ▁further ▁stim ulation . ▁ ▁Equ ally , ▁if ▁sexual ▁stim ulation ▁stops ▁before ▁org asm , ▁the ▁physical ▁effects ▁of ▁the ▁stim ulation , ▁including ▁the ▁v aso cong estion , ▁will ▁sub side ▁in ▁a ▁short ▁time . ▁Re pe ated ▁or ▁prolong ed ▁stim ulation ▁without ▁org asm ▁and ▁ej ac ulation ▁can ▁lead ▁to ▁dis com fort ▁in ▁the ▁test es ▁( cor respond ing ▁to ▁the ▁sl ang ▁term ▁" blue ▁balls "). ▁ ▁After ▁org asm ▁and ▁ej ac ulation , ▁men ▁usually ▁experience ▁a ▁ref ract ory ▁period ▁character ised ▁by ▁loss ▁of ▁ere ction , ▁a ▁subs idence ▁in ▁any ▁sex ▁flush , ▁less ▁interest ▁in ▁sex , ▁and ▁a ▁feeling ▁of ▁relax