Its officials say the government has failed to meet a key target to recruit extra staff.

The college has also warned that plans to boost midwife numbers by 50% by 2009 will fail unless action is taken to make posts more attractive.

There is a challenge to meet our target of increasing midwives in the NHS but we are determined to do that Health Minister Jacqui Smith

Hundreds of midwives are leaving their jobs each year and vacancy rates are at record rates, according to the college.

The shortages mean few women have the sole attention of a midwife if they give birth on the NHS.

Midwives themselves warn that the shortages may be putting patients at risk.

Recruitment targets

The government has pledged to recruit 2,000 extra midwives by 2004 and a total of 10,000 over the next seven years.

As part of that programme of expansion, ministers aimed to encourage 500 additional staff to take up posts in the NHS by September.

However, figures obtained by the BBC show that it has failed - the overall number of midwives has actually fallen since the target was set.

Vacancy rates have increased everywhere apart from London, where empty posts were already at critical levels.

The royal college says the shortage is putting extra pressure on existing staff, many of whom are now also considering quitting.

Jon Skewes, director of employment relations at the RCM, said: "The government was making progress towards the 500 figure but our latest information shows in the last six months they've been slipping back and there are now 45 fewer midwives.

Vacancy rates are increasing everywhere Jon Skewes, RCM

"It is clear from our own staffing survey that vacancy rates are increasing everywhere and not just in London and the south-east," he told BBC News Online.

The college has called for extra money for midwives.

"Midwives clearly have to be valued much better than they are. The most that quite qualified midwives can earn in the NHS is about �25,000," said Mr Skewes.

"We want to see the government investing in a new pay system for the NHS which is more than three years in negotiation and it is about time it delivered for midwives."

Short-term problems

Health Minister Jacqui Smith said the government was determined to meet its targets.

"We may be seeing some short-term problems but overall we have seen considerable increases," she told the BBC.

"The trend is in the right direction. What's more important, we are taking action to make sure that continues - more midwives in training, action to bring back into the profession midwives who've left it.

"I know there is a challenge to meet our target of increasing midwives in the NHS but we are determined to do that."