The majority of pregnancies have good outcomes despite exposure to potential hazards along the way. However, 2.5 per cent of babies have a significant anomaly at birth (Sokal et al. 2014), ranging from an extra digit to a major heart defect. The proportion of babies being born with abnormalities has reduced considerably in recent years. There are many possible reasons for this, including an increased awareness of the many potential risks that babies can be exposed to in utero, enabling some to be avoided. In addition, recent advances, such as the ability to discover the genetic profile of the fetus and to visualise the fetus as it is developing, enable parents to make decisions regarding therapeutic abortion if an abnormality is detected.