Royal College of Obstetricians and Gynaecologists (RCOG) president Dr Ranee Thakar said complex births were a “major factor”.

“We are seeing national rising rates of obesity and people choosing to have children at a later state in their life, both of which can increase the chance of complications,” she said.

The likelihood of a Caesarean increased with the mother’s age.

And for those aged over 39, it was the most common method of delivery.

Most women under 30, meanwhile, had “spontaneous” vaginal births, without medical intervention to start labour.

A third of all deliveries were induced, meaning labour was started using artificial methods such as a hormone drip or a pessary.

The RCOG does not promote one form of birth over another.