A woman has received £30,000 compensation after surgeons left a swab inside her body when she had a Caesarean section, lawyers said.
Amy Callaghan, 28, of Rugby, Warwickshire, had emergency surgery on Christmas Day in 2007 to remove the swab, which she said left her in agony.
Miss Callaghan gave birth on 2 December 2007 at Coventry's University Hospital.
It has accepted liability for the blunder and offered its "sincere apologies".
Irwin Mitchell Solicitors, representing Miss Callaghan, said she began to experience "terrible pain" two weeks after the birth and found a lump in her abdomen.
A Christmas Eve X-ray revealed the swab inside her body and she returned the following day to have it removed.
Miss Callaghan said: "The birth of my first child should have been a time of great excitement but instead it turned into a nightmare.
"I was so ill after Tegan was born. I was trying my best to be a good mum but I was in such agony that I hardly had the strength to look after myself, let alone her.
"I'm very angry that all the pain and heartache I suffered was caused by such a basic error which should never have been allowed to happen."
University Hospitals Coventry and Warwickshire NHS Trust paid the £30,000 sum to Miss Callaghan in an out-of-court settlement.
Andy Hardy, chief executive of the Trust, said: "We apologise to Amy Callaghan for this mistake in 2007 and the distress caused to her because of it.
"This was unacceptable and we immediately investigated it and reported it to the National Patient Safety Agency.
"In theatres we now follow the World Health Organisation's Surgical Safety Checklist, which requires at the end of each operation that the staff make sure instrument, sponge and needle counts are all correct."
He added: "Earlier this year, our maternity services were awarded a Level 2 against the NHS Litigation Authority's Clinical Negligence Scheme For Trusts, as the Trust showed the provision of safe, high-quality care for mothers and babies."
Guy Forster, a medical negligence expert from Irwin Mitchell Solicitors, said: "Mistakes like this simply should not happen.
"We very much hope that this incident has prompted the hospital to re-evaluate its safety procedures during surgery to ensure that lessons are learned and such an error does not happen in the future."