The impact of maternal experience of violence and common mental disorders on neonatal outcomes: a survey of adolescent mothers in Sao Paulo, Brazil

930 consecutive pregnant teenagers, admitted for delivery were recruited. Violence was assessed using the Californian Perinatal Assessment. Mental illness was measured using the Composite International Diagnostic Interview (CIDI). Apgar scores of newborns were estimated and their weight measured.21.9% of mothers reported lifetime violence (2% during pregnancy) and 24.3% had a common mental disorder in the past 12 months. The exposures were correlated and each was associated with low education. Lifetime violence was strongly associated with Common Mental Disorders. Violence during pregnancy (PR = 2.59(1.05–6.40) and threat of physical violence (PR = 1.86(1.03–3.35) and any common mental disorders (PR = 2.09 (1.21–3.63) (as well as depression, anxiety and PTSD separately) were independently associated with low birth weight.Efforts to improve neonatal outcomes in low income countries may be neglecting two important independent, but correlated risk factors: maternal experience of violence and common mental disorder.Both the experience of violence and antenatal depression may be risk factors for adverse neonatal outcomes, particularly low birth weight. A review of studies conducted in the USA and Europe[1] showed a weak, but significant, association between abuse during pregnancy (physical, sexual or emotional) and low birth weight (pooled OR = 1.4, 95%CI = 1.1–1.8) Developing country studies are rarer, but with results in the same direction [2-4]. For antenatal mental disorder, the pattern of findings suggests that socio-economic status may be an effect modifier, with associations with low birth weight only being apparent in more deprived communities [5-9]. Although previous studies have looked at the effect of these exposures separately, they are, in fact, closely related. In a meta analysis the weighted odds ratios for the association of different mental disorders with violence among women varied from 3.5 to 5.6 [10]. The aim of this study is to describe, among disadv