David Cameron's failure to honour a promise to introduce an extra 3,000 midwives in England is putting the safety of mothers and unborn babies at risk, according to the leader of the Royal College of Midwives.

Cathy Warwick said numbers of the health professionals have not kept pace with the birthrate in England, which has risen 22% in the past two decades, affecting quality of care.

"Before he came into power David Cameron promised to increase the number of midwives in England by 3,000, describing them as 'overworked and demoralised'. Sadly, since then little has been done by this Government for maternity services," the RCM's general secretary told the Sunday Mirror.

The college has launched an e-petition urging 5,000 extra midwives be trained to keep up with the added pressures, which include growing numbers of obese and older pregnant women.

Mrs Warwick added: "When Mr Cameron was pressed to honour his pre-election promise, the response was more midwives were not needed because the birth rate was falling. Well, the birth rate figures came out in July and they had rocketed.

"I have become so concerned about the shortage of midwives that I have lodged an e-petition with Parliament calling for the Government to set a target of 5,000 more NHS midwives in England.

"Without this increase in midwife numbers and investment I have real fears that our maternity services could be heading towards a point where not only the quality of care is threatened, but safety as well.

"The NHS has to save money, but, this should not be at the expense of safety and the quality of care."