Introduction Delayed access to antenatal care (“late booking”) is linked to increased mortality and morbidity for mother and baby: 17% of recent direct and indirect maternal deaths were women who booked for care after 22 weeks; had missed >4 routine antenatal visits or did not seek care at all. We interviewed a cohort of late-booking pregnant women to explore the reasons for delayed access, and their attitudes/expectations towards antenatal care.

Method We purposively sampled women booking >19 weeks gestation from hospital and community antenatal clinics. We conducted semi-structured, face-to-face, taped individual interviews in women's homes, hospital clinics and children's centres. Data was transcribed, coded and organised using NVivo software, conducting an inductive, iterative, thematic analysis with independent verification.

Results 27/80 women consented to interview. Participant demographics showed greater diversity (age, parity, socioeconomic status, and ethnicity) than ‘typical’ late booking patients reported elsewhere. Three key groups were identified, with explanatory subthemes, relating to personal attitudes and behaviors, knowledge and experience, and professional and organisational factors: 1) the ‘not knowers’: ‘not realisers’ (absence of classic symptoms, misinterpreters); ‘not believers’ (age, subfertility, using contraception, lay hindrance); 2) the ‘knowers’: the ‘avoiders’ (ambivalence, fear, DIY care); the ‘postponers’ (fearful, on the move, undecided, not valuing antenatal care, DIY care); 3) The ‘delayees’ (professional and system failures, knowledge and empowerment issues).

Conclusion In the largest UK qualitative study to date we have identified service-user and healthcare factors for late booking which should inform service configuration to mitigate social exclusion and minimise adverse outcomes.