Heroin misuse in pregnancy is a significant health and social problem, and it can have an adverse effect on the mother and the baby. Although heroin and methadone have no specific teratogenic potential, 48–94% of children exposed in utero will have neonatal abstinence syndrome (NAS). The primary aim of this case report is to raise awareness of NAS among clinicians and to remind them that although very common, it is not inevitable. The risk of NAS can be further minimised by offering comprehensive and co-ordinated antenatal care that addresses the various biopsychosocial needs of the pregnant woman. Further, a brief description of NAS and a review of evidence in the field of management of opioid misuse in pregnancy, as relevant to this case, are provided. We have also included the patient’s own reflections on her pregnancy and treatment.