Objectives To analyse which dysmorphic features are most recognised in newborns with Down syndrome (DS). Furthermore to evaluate the communication techniques used by clinicians to inform parents about the postnatal diagnosis and compare these to current best practice guidelines. Study design Prospective study of a birth cohort of newborns with DS born between 1 January 2003 and 31 December 2006 registered by the Dutch Paediatric Surveillance Unit (DPSU). Results A total of 586 children with trisomy 21 were analysed. Most recognised dysmorphic features in DS newborns were ‘upslanted palpebral fissures’ (74.1%; n = 426), ‘hypotonia’ (73.7%; n = 424) and ‘epicanthic folds’ (68.5%; n = 394). The majority of parents were informed about the suspected diagnosis on the day of birth (76.5%; n = 390). Hospital deliveries had a significantly earlier suspected diagnosis (mean age 3–4 days) compared with home deliveries (mean age 7 days) (P < 0.05). In 10% (n = 44), paediatricians described dissatisfaction with the first conversation with parents. In 88.9% (n = 499) parents were both present when the diagnosis was told, however the child was not present during the conversation in 51.3% (n = 288). In 10.8% (n = 61) parents were not informed about local parent support groups or community resources. Conclusion DS is still often diagnosed after birth, usually on the first day of postnatal life. Most identified clinical features were upslanted palpebral fissures, epicanthic folds and hypotonia. Special attention for recognition of all present clinical features is needed for early diagnosis. Appropriate communication with the parents of the message that their child has DS can be difficult. Guidelines can help to make counselling easier and more effective, which in turn may increase parental satisfaction. Not all recommendations for the first conversation with parents were fully implemented in Dutch clinical practice.