Prolonged non-nutritive suckling habits (finger and pacifier) (PNNSH) can indicate children's emotional and behavioral difficulties. Our aim was to evaluate the association of such habits with emotional and behavioral problems in schoolchildren, taking also into account birth and school age conditions.

Data were collected at birth and school age from children of two Brazilian cities, São Luís (SL) and Ribeirão Preto (RP). the Strength and Difficulties Questionnaire (SDQ) was applied to 790 schoolchildren in RP and 673 in SL to identify Emotional Symptoms, Conduct Problems, Hyperactivity and Peer Problems. the children were classified as “normal” and “abnormal” depending on the score for each scale. PNNSH were considered to be prolonged when they lasted 36 months or more. Crude and adjusted prevalence ratios (PR) were calculated by Poisson regression.

The overall proportion of PNNSH was 47.6% and 19.6%, and of the proportion of symptoms was 38.2% and 34.7% in RP and SL, respectively. Abnormal symptoms were: Emotional Symptoms, RP = 54.0%, SL = 57.4%; Conduct Problems, RP = 34.7%, SL = 48.0%; Hyperactivity, RP = 26.4%, SL = 32.5%; Peer Problems, RP = 27.2%, SL = 26.5%. After adjustment for socio-demographic factors, PNNSH was a risk factor for emotional symptoms (PR = 1.17), conduct problems (PR = 1.43) and hyperactivity (PR = 1.55) in RP and marginally for peer problems (PR = 1.33, 95%CI 1.00–1.77) in SL. Girls were protected against conduct problems and hyperactivity in both cities.

PNNSH were associated with behavioral and emotional symptoms at school age in RP children and borderline associated with peer problems in SL. Girls were protected from behavioral problems in both cities