The average birth weight of babies has been increasing for the past 30 years, but now there is a more pronounced increase in excessive birth weights. What is the reason for this, and is there a difference between a "bonny", healthy big baby and one that is at risk of complications because of its size? Jane speaks to Dr. Siobhan Quenby, Consultant Obstetrician at the Liverpool Women’s Hospital, and Gail Johnson, a midwife and Education and Professional Development Advisor from the Royal College of Midwives.