Background Clinical guidelines on instrumental deliveries are mainly skill based. The objective of this study was to identify factors which influence clinicians' decision making in conducting an instrumental delivery.

Methods The study has utilised a qualitative case-study approach comprising observation of the decision-making process during deliveries and follow-up interviews with clinicians. Interview data were transcribed and used alongside observational notes to analyse decision making in each case.

Results Data were collected from 23 cases, the majority of which (n=16) were forceps deliveries. A range of factors related to equipment, training and hospital culture were identified as being discouraging to the use of ventouse.

Conclusion Hospital context and culture have a central role in influencing clinician's decision making. Understanding these factors is a crucial first step in assessing appropriate practice and identifying interventions to change practice.