A prospective population study indicates that low birthweight and being born to a teenage mother are independent risk factors for increased risk of suicide in later life, according to an article in the September 25th issue of the Lancet. The study also shows how being born fourth or more in sibling order and poor maternal socio-economic status are associated with an increased risk of suicide attempt.

Previous research to assess possible associations between adverse neonatal, obstetric, and maternal conditions and heightened suicide risk in adolescents has been sparse, yielding conflicting results. No previous study had simultaneously analyzed specific obstetric and neonatal risk factors and maternal psychosocial and socioeconomic conditions in relation to suicide and attempted suicide in children and adolescents.

Dr. Danuta Wasserman and colleagues prospectively followed over 700,000 young adults born in Sweden between 1973 and 1980. The investigators assessed the proportion of attempted and actual suicides between 10 and 26 years of age.

The overall suicide rate in Sweden in 1999 (when follow-up in the study finished) was around 20 per 100,000 population. Low birthweight (2 kg or less) children and children born to teenage mothers were more than twice as likely to commit suicide as the reference population (majority had birthweight around 3-5kg at birth and maternal age 20-29 years at delivery).

Significantly raised risk for attempted suicide was reported for individuals of short birth length (hazard ratio 1・29); born fourth or more in birth order (1・79); born to mothers with a low educational level (1・36). The investigators also showed that older maternal age (29 years or more at delivery) was protective against suicidal behavior of their children.

Dr Wasserman commented, "The reported associations of fetal growth restriction and adverse maternal conditions with suicidal behavior could be due to parental psychiatric disorders and aggregation of suicide in the family. Maternal mental ill-health might affect fetal growth and socioeconomic position, increase the risk of teenage pregnancies, and exacerbate that of psychiatric disorders in their offspring, which further heightens the risk of suicidal behavior".

In an accompanying commentary, Maria A Oquendo, MD, concluded "... {the} findings supply another step towards the construction of a model for the understanding of suicidal behavior. Maternal and perinatal factors may be determinants of a diathesis for suicidal behavior. The identification of effects of intrauterine environment and perinatal environment on suicidal behavior thus gives us another venue in suicide prevention. Indeed, these data illustrate that good mothering begins well before the day of birth."