Story: Inventions, patents and trademarks

The Baeyertz tape

The Baeyertz tape

The Whanganui obstetrician and gynaecologist Dr John Baeyertz needed an accurate and easy way to determine when a pregnant woman would give birth. He developed a measuring tape using data from babies conceived by artificial insemination, so the date of conception was known exactly. The Baeyertz tape was first patented in 1982 and is still widely used around the world. It is shown here calculating the arrival date of Liam Cooper, who was born on schedule in October 2009.

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How to cite this page:

Mark Derby, 'Inventions, patents and trademarks - Patents in New Zealand', Te Ara - the Encyclopedia of New Zealand, (accessed 23 May 2024)

Story by Mark Derby, published 11 Mar 2010, updated 1 Feb 2015