) ▁is ▁a ▁subset ▁of ▁the ▁per ine um . ▁ ▁The ▁per ine um ▁is ▁an ▁er ogen ous ▁zone ▁for ▁both ▁males ▁and ▁females . ▁Per ine al ▁tears ▁and ▁epis iot omy ▁often ▁occur ▁in ▁child b irth ▁with ▁first - time ▁deliver ies , ▁but ▁the ▁risk ▁of ▁these ▁inj uries ▁can ▁be ▁reduced ▁by ▁prepar ing ▁the ▁per ine um , ▁often ▁through ▁mass age . ▁The ▁word ▁per ine um ▁ ▁der ives ▁from ▁late ▁Latin , ▁from ▁Greek ▁ π ε ρ ί ν ε ος ▁per ine os ▁per inae on , ▁peri -, ▁around ▁+ ▁in ein ▁to ▁dis charge ▁or ▁def ec ate . ▁ ▁Str ucture ▁The ▁per ine um ▁is ▁generally ▁defined ▁as ▁the ▁surface ▁region ▁in ▁both ▁males ▁and ▁females ▁between ▁the ▁pub ic ▁sym ph ysis ▁and ▁the ▁c oc cy x . ▁The ▁per ine um ▁is ▁below ▁the ▁pel vic ▁dia ph rag m ▁and ▁between ▁the ▁legs . ▁It ▁is ▁a ▁diam ond - sh aped ▁area ▁that ▁includes ▁the ▁an us ▁and , ▁in ▁females , ▁the ▁v ag ina . ▁Its ▁definition ▁var ies : ▁it ▁can ▁refer ▁to ▁only ▁the ▁super f icial ▁structures ▁in ▁this ▁region , ▁or ▁it ▁can ▁be ▁used ▁to ▁include ▁both ▁super f icial ▁and ▁deep ▁structures . ▁The ▁per ine um ▁corresponds ▁to ▁the ▁out let ▁of ▁the ▁pel vis . ▁ ▁A ▁line ▁drawn ▁across ▁the ▁surface ▁connecting ▁the ▁is ch ial ▁tub eros ities ▁div