NHS sonographers, who perform vital ultrasound scans at 12 and 20 weeks of pregnancy and diagnose cancers, have warned that a shortage of staff is causing delays to pregnant women and cancer patients. One in four job posts are vacant in England, with even greater shortages reported in the north west and south east. The Society of Radiographers, representing sonographers in the UK, said demand for ultrasound has increased due to increased training but insufficient staff are being trained. The government has responded by expanding services and expanding community diagnostic centres to local communities. Dr. Jenny Barber, consultant obstetrician and vice president for clinical quality at the Royal College of Obstetricians and Gynaecologists, called the high vacancy rate "very concerning". She suggested that significant investment in the maternity workforce was needed.