June 7, 2026
By Bunmi Sofola
IMAGINE when your pregnancy is scanned for the first time so you could see your precious baby growing in the womb, suddenly its whole body gives a shudder and the foetus appears to jump. Such a movement is known as the startle reflex; and the scan described above are from photographs from scans that were taken by Peter Hepper, a professor of psychology at Queens University, Belfast, an expert on the effects of alcohol on unborn babies.
It was once believed that the occasional glass of wine in pregnancy is fine – though alcohol rapidly reaches your baby through your blood-stream and across the placenta. But studies such as Professor Hepper’s could prove this belief wrong and that drinking alcohol at all while pregnant could affect your baby. The Prof studied 40 pregnant women. Half said they would not give up alcohol in their pregnancy, half said they would; those who did drink had one to four units of alcohol – around four small glasses of wine every week.
Each woman was scanned seven times at various stages of their pregnancy. The results were astounding. By 18 to 20 weeks – when the foetal brain becomes more developed – the startle reflex in the foetuses of the non-drinking mothers had disappeared. But the reflex was still present in the foetuses of the women who drank, and was visible even at 35 weeks. What does this mean? Prof. Hepper explains: “The startle reflex was still present in the foetuses of women who drank, and was visible even at 35 weeks. What does this mean? Prof. Hepper explains: “The startle reflex is one of the first movements that a foetus performs, usually in response to loud noises. It is a very primitive response. Of course, this sudden jerk is not the way we move in later life. As the foetus mature, different parts of the brain develop to control movement, so gradually, the startle reflex disappears.
