Continuity mistake: Jim Dale and Anita Harris think that Barbara Windsor is going to jump off the roof and race across the road into the nurse's block. We see Anita Harris is wearing dark seamed hosiery as she runs up the stairs. A few minutes later she hangs down from the roof and the seams have disappeared from the backs of her legs. (00:59:00 - 01:01:55)
Plot hole: When Mr. Bigger arrives at the hospital, he slides out of the trolley. Look carefully : he was not in the trolley.
Other mistake: When Dr Kilmore holds the test tube of Mr Roper's urine sample over the Bunsen burner, the test tube catches fire and Dr Kilmore says he thinks that Mr Roper is producing neat scotch. In the next shot, Dr Kilmore is now holding the test tube which ought to be too hot to touch.
Character mistake: At the hospital, Mr Bigger's surname is misspelt as "Biggir" on the name tag on his bed.
Continuity mistake: When Charles Hawtrey is doing keep-fit with the other expectant mothers, you can see next to him there is a lady with a red dressing gown, and the pillow she has her head on is next to the wall. But in the next shot, the pillow has moved away from the wall and a handbag appears from nowhere.
Continuity mistake: When Mr Bigger is sorting out the pillow in his bed, you can see that Mr Barron opens his eyes in the bed next to him. In the next shot, Mr Barron now has his eyes closed and he opens them a second time.
Continuity mistake: When Dr Kilmore is in the nurse's bath after he landed in there after crashing through the window, the washing line on his uniform keeps disappearing and re-appearing between shots.
Continuity mistake: When Nurse May is standing up and screaming on the balcony after seeing Dr Kilmore on the roof of the nurses' home, you can see an ambulance in the car park of the hospital and by it are the two ambulance drivers (Sam and Henry) and a couple behind them. But in the next shot, Sam is now walking towards Henry as well as the other couple.
Continuity mistake: When Mr Biddle is telling Mr Bigger about his appendix operation, Mr Bigger can be seen with his arms by the side of his bed. In the next shot, he now has his hands clasped together on the bed sheet.
Continuity mistake: When Dr. Tinkle tells Dr. Kilmore to sit down during the meeting with Sir Edmund Burke, you can see Dr. Tinkle put his hands together, but in the next shot his left hand is resting on the desk.
Continuity mistake: When Mr Bigger is being stretchered through some double doors following his x-ray, we see a close-up of him and you can see the pink uniform of a nurse behind the trolley. But when Dr Kilmore knocks Mr Bigger off the trolley, the nurse appears after the trolley has been wheeled out of the double doors.
Continuity mistake: When the ambulance arrives at the hospital, it parks at an angle in relation to the door. In the next scene, the ambulance is in directly in line with the entrance.