However, they still had a 24 per cent higher relative risk of fine motor difficulties, which involve movements such as drawing, holding a pencil and handling small objects.The findings raise questions about whether the timing of night work matters, although researchers could not establish whether stopping night shifts would prevent developmental problems.UK experts welcomed the study but called for further research. Professor Kevin McConway, Emeritus Professor of Applied Statistics at the Open University, said that while the increased risks sounded alarming, the actual rise in the number of children affected was relatively small.Professor Debra Skene, Professor of Neuroendocrinology at the University of Surrey, said: “We need more research to look at the effects of shift work on working pregnant women.”