Covid 19 Delta outbreak: Auckland University academic slams colleague's work around Covid vaccine as being 'wrong'

An Auckland University department head is publicly distancing himself from a colleague's paper on the Covid vaccine saying it has a "major error" which is causing unnecessary angst amongst expectant parents.

But the co-author, Dr Simon Thornley, a senior lecturer of epidemiology at the University of Auckland, told the Herald today a correction was made as soon as the paper was published last week as the figure was "clearly unrealistic".

The article has since been retracted.

University of Auckland head of population health Professor Robert Scragg, in an email to staff, said the paper published in an anti-vaccine journal wrongly concluded that between 80 to 90 per cent of pregnant women will miscarry if they had the Covid-19 vaccine.

Scragg called on Thornley and co-author Whanganui-based Dr Aleisha Brock to immediately publicly retract their article because of the anxiety it is creating for expectant parents and those planning to have a child.

The findings contradicted several other papers which found the vaccine created no additional risk to pregnant women, he said.

Scragg claims Thornley and Brock used the incorrect denominator when reaching their conclusion.

A paper published in the New English journal based on an analysis of the same data Thornley and Brockley used concluded that 14.1 per cent of vaccinated women had a miscarriage up to 20 weeks - similar to the number of unvaccinated women who miscarry, he said.

Another large study looking at the safety of the Covid-19 vaccine in early pregnancy by Kharbanda and colleagues which was published in JAMA also found that the vaccine was not a risk factor for miscarriage.

"Collectively, the results from the Zauche and the Kharbanda papers show that Covid-19 vaccine does not increase the risk of miscarriage and that women who are currently pregnant or planning to get pregnant can safely receive the vaccine."

Thornley said the figure that the risk was eight times as great was "clearly unrealistic" and the true risk was "much, much lower".

"But I think we are still in the early days and we have very few studies to point us in the right direction."