Backgound: Perinatal Mental Illness (PMI) is a key cause of maternal mortality and morbidity in the UK, with one goal of midwives to identify those at risk during pregnancy. At present, the system of preliminary identification of existing PMI in the UK involves the midwife asking pregnant women the Whooley questions at the antenatal booking interview. Aim: To explore midwives experiences of asking the Whooley questions with pregnant women. Method: A qualitative interpretive study explored midwives’ (n = 8) experiences of asking the Whooley questions in one maternity unit in England (UK). Data were gathered through semistructured interviews and analysed using Framework Analysis (FWA). Findings: Themes and subthemes identified included: (1) no clear understanding of purpose, (1a) discomfort when disclosure occurs, (2) feeling pressurised for time, (3) resultant dissatisfaction and frustration; (3a) lack of knowledge and how to refer, (3b) lack of training around PMI, (3c) relying on experience and use of intuition. Discussion: The development and evaluation of an education curriculum to prepare midwives to effectively use case-finding instruments such as the Whooley questions to identify pregnant women at risk is required.