The third-year Otago Polytechnic student wants to raise awareness of the waste in modern lives by turning disposable nappies into garments.
She has stockpiled thousands of new disposable nappies to create hundreds of items, such as jackets, pants, sleeping bags and duvets - "everything you would normally wash".
The pieces will be displayed in a mock shop during the end-of-year School of Art Site exhibition, to raise awareness of the waste created by disposable products.
Manufacturers argued disposables were as sustainable as reusable nappies when the water used to wash them was taken into account, she said.
However, during her work as an au pair in Chicago, she saw how many nappies were used daily and thrown away.
As one nappy took between 75 and 500 years to break down in landfill, and one baby would use about 6000 nappies, she had been inspired to change the public's belief that they were acceptable.
In a bid to publicise her message, Miss O'Leary sent a jacket, made with about 20 nappies, to United States' talk show host Ellen DeGeneres in the hope it would feature on her television show.
After the exhibition, Miss O'Leary plans to give the nappies to awareness groups in the hope they will use them to promote the use of reusable cloth nappies.
