to quantify to what extent evidence-based health behaviour topics relevant for pregnancy are discussed with clients during midwife-led prenatal booking visits and to assess the association of client characteristics with the extent of information provided.quantitative video analyses.173 video recordings of prenatal booking visits with primary care midwives and clients in the Netherlands taking place between August 2010 and April 2011.thirteen topics regarding toxic substances, nutrition, maternal weight, supplements, and health promoting activities were categorized as either 'never mentioned', 'briefly mentioned', 'basically explained' or 'extensively explained'. Rates on the extent of information provided were calculated for each topic and relationships between client characteristics and dichotomous outcomes of the extent of information provided were assessed using Generalized Linear Mixed Modelling.our findings showed that women who did not take folic acid supplementation, who smoked, or had a partner who smoked, were usually provided basic and occasionally extensive explanations about these topics. The majority of clients were provided with no information on recommended weight gain (91.9%), fish promotion (90.8%), caffeine limitation (89.6%), vitamin D supplementation (87.3%), physical activity promotion (81.5%) and antenatal class attendance (75.7%) and only brief mention of alcohol (91.3%), smoking (81.5%), folic acid (58.4) and weight at the start of pregnancy (52.0%). The importance of a nutritious diet was generally either never mentioned (38.2%) or briefly mentioned (45.1%). Nulliparous women were typically given more information on most topics than multiparous women.although additional information was generally provided about folic acid and smoking, when relevant for their clients, the majority of women were provided with little or no information about the other health behaviours examined in this study. Midwives may be able to improve prenatal health promotion by providing more extensive health behaviour information to their clients during booking visits.