Aims To investigate the possible linkages between deliveries, abortions and subsequent nicotine dependence, alcohol problems and use of cannabis and other illegal drugs from the ages of 15–27 years.
Methods Data were gathered as part of the Young in Norway Longitudinal Study, an 11-year follow-up of a representative sample of Norwegian adolescents and young adults.
Design, setting and participants Information was obtained on (i) the history of childbirths and induced abortions for the participants between the ages of 15–27 years; (ii) measures of nicotine dependence, alcohol problems and use of cannabis and other illegal drugs; and (iii) socio-demographic, family and individual confounding factors.
Results Those who had had an abortion had elevated rates of substance use and problems. Those who gave birth to a child had reduced rates of alcohol problems and cannabis use. These associations persisted after control for confounders. However, those women who still lived with the father of the aborted fetus were not at increased risk.
Conclusions Abortion in women may, under some circumstances, be associated with increased risk of nicotine dependence, alcohol problems and use of cannabis and other illegal drugs. The birth of a child may reduce the use of some substances.