Jane Greaves, 46, said low staffing levels meant she was unable to leave the unit during 12-hour shifts.
Miss Greaves, who has worked at the birth centre at Pinderfields since it opened in September 2016, said she does not go to the toilet at work, adding: “You just ignore it because you know you have got to leave the unit. You can’t just say to a woman ‘stop pushing, I’m going for a wee.”
Miss Greaves, a midwife for 16 years, said when the centre opened it had three midwives and two health carers, but now has just two midwives and one health carer.
She said she has informed management at least 49 times about problems of high workload and not enough staff at the unit.
Miss Greaves, of Wakefield, said she was ill after working on December 31 and went to A&E at Pinderfields and was sent to see a urologist, who said she was not emptying her bladder often enough and had contracted a kidney infection.
She said she was give a seven-day sick note.
Miss Greaves said she had a total of 14 days off sick in the 12 months from January 2016 to January 2017.
She was told she was being dismissed immediately due to her sickness record by the trust’s head of midwifery on March 15.
Miss Greaves added: “Work is all I have got so to take it away from me is horrendous.”
A petition has been launched at the trust and Unison is calling for her to be reinstated.
Adrian O’Malley of Unison said: “Jane’s dismissal is the most unjust I have witnessed in over 35 years as a steward at Pinderfields Hospital.
“She has registered 49 times that she has been so busy she could not take a break on her 12 hour night shifts.
“She works on a department where there is no staff toilet and was off sick due to a urinary infection which led to her attending the emergency department.
“Her record of 14 calendar days off in the last 12 months is better than the trust average and still they sacked her.
“It’s absolutely outrageous that a trust which is advertising for midwives has dismissed a dedicated member of staff of 18 years standing. Quite rightly her colleagues are disgusted and are petitioning the chief executive to get her reinstated.”
Yvonne Rowlan, assistant director of nursing and midwifery, at The Mid Yorkshire Hospitals NHS Trust, said: “We are dedicated to providing excellent patient care and supporting our staff to do this.
“In every aspect of our work we adhere to a set of core values which underpin not only the care we give to our patients but also the care and respect we show to each other as members of staff.
“The trust is unable to comment on HR issues regarding individual employees.”