The incident occurred in June 2010 when the two women had given birth to their children by caesarian section.
The midwife immediately realised her mistake and contacted the duty physician who in consultation with a specialist, placed the woman on a course of anti-viral medicines to combat any infection.
She was also told not to breastfeed her child.
The woman was given an HIV test and when the results were returned several months later, it was concluded that she had not been infected with HIV.
The incident was duly reported by the hospital to the Swedish Health and Welfare Board (Socialstyrelsen) who concluded that the ward had not followed existing guidelines.
The hospital has since notified that it made immediate changes to its routines after the incident to ensure that used needles are disposed of immediately after use.
The board has instructed the hospital to submit a report regarding its needle management routines.
The report is to be filed by March 18th.