So here’s the deal y’all:
There were some studies, most notably a study of a large european population dataset, that showed a very small increase in risk of autism among kids of women who took acetaminophen in pregnancy. There are also numerous studies showing no association, and a study of 2.4 million children from Sweden found no link at all between autism and acetaminophen use.

@petrelharp@ecoevo.social
Data science, ecology & evolutionary biology and population genetics at University of Oregon. He/him/his. Rearranges to spell my name.
Springer now demand that your pre-acceptance version of a paper on the arXiv comes with a disclaimer:
“This preprint has not undergone peer review (when applicable) or any post-submission improvements or corrections. The Version of Record of this article is published in [insert journal title], and is available online at https://doi.org/[insert DOI]”."
and forbids you from putting the version accepted on the arXiv under an OA license:
"The rights granted to the Author with respect to the Accepted Manuscript are subject to the conditions that (i) the Accepted Manuscript is not enhanced or substantially reformatted by the Author or any third party, and (ii) the Author includes on the Accepted Manuscript an acknowledgement in the following form, together with a link to the published version on the publisher’s website: “This version of the article has been accepted for publication, after peer review (when applicable) but is not the Version of Record and does not reflect post-acceptance improvements, or any corrections. The Version of Record is available online at: http://dx.doi.org/[insert DOI]. Use of this Accepted Version is subject to the publisher’s Accepted Manuscript terms of use https://www.springernature.com/gp/open-research/policies/accepted-manuscript-terms”. Under no circumstances may an Accepted Manuscript be shared or distributed under a Creative Commons or other form of open access licence."
So Springer is saying it has control over how people use papers on the arXiv: "Use of this Accepted Version is subject to the publisher’s Accepted Manuscript terms of use."
I knew none of this when I submitted my paper, nor when I uploaded my updated paper to the arXiv.