Source:http://linkedlifedata.com/resource/umls/id/C0014586
MSH: An incision of the posterior vaginal wall and a portion of the pudenda which enlarges the vaginal introitus to facilitate delivery and prevent lacerations.,NCI: A surgical widening of the introitus by cutting into the musculature of the maternal perineum with a linear midline or oblique incision so as to facilitate vaginal childbirth.