<prompt> Answer this question truthfullyWhich nerve can be blocked with local anesthetic during childbirth or minor surgeries of the vagina and perineum, and what are the landmarks used for injection?  <response>: <reason> The pudendal nerve can be blocked with local anesthetic during childbirth or minor surgeries of the vagina and perineum using the ischial spine and sacrospinous ligament as landmarks for injection. 