In childbirth many women who have vaginal deliveries sustain perineal trauma with decisions being made that some spontaneous tears require suturing.Relying on past experiences and knowledge midwives make these clinical decisions.To date these decisions are guided by little researched evidence.This mixed methods study aimed in Phase One to identify cues and related factors midwives use when making decisions to suture or not suture perineal and associated trauma and in Phase Two to evaluate the content validity of the identified cues and related factors.The exploratory descriptive qualitative Phase One using Critical Decision Method in-depth interviews with 18 experienced midwives identified the cues of bleeding and trauma with their accompanying specific attributes, and woman-centred factors considered when deciding whether or not to suture perineal and associated trauma.In Phase Two a panel of experienced midwives evaluated the content validity of the identified cues, attributes and factors by a structured questionnaire that assessed their necessity and sufficiency.Analysis showed more than 89% of the panel judged the cue of bleeding and its attributes type, flow, amount, effect of application of pressure or ice as being necessary to assess.With the other main cue, birth trauma, and its attributes trauma sites, trauma types, dimensions of trauma, types of tissue, alignment of tissue, oedema, bruising being necessary.The seven woman-centred related factors were judged necessary by 94% of panel members and 78% judged the combination of all cues and attributes for bleeding, birth trauma and related factors sufficient for making the decision to suture or not.These validated cues and related factors have the potential to guide clinical decision-making to suture or not suture and be developed into a clinical inventory.Further they clarify working midwifery practice knowledge that can be further researched to provide evidence-based practice.