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Kōrero: Inventions, patents and trademarks

The Baeyertz tape

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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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Me pēnei te tohu i te whārang

Mark Derby, Inventions, patents and trademarks – Patents in New Zealand, Te Ara – the Encyclopedia of New Zealand, https://teara.govt.nz/mi/photograph/25393/the-baeyertz-tape (accessed 4 June 2026).

He kōrero nā Mark Derby, i tāngia i te 11 May 2010, updated 1 February 2015.