Word of caution on latest UK vaccine & pregnancy post

There is a reason I ask for peer review, so thank you to reader Brian Mowrey for his comment in the last post. Brian correctly points out that my previous estimate that vaccinated women should have stillbirth rates 33% lower than unvaccinated women may not be appropriate when we look only at December. Women given birth in December will be more likely to have been vaccinated earlier in their pregnancy than women giving birth earlier in the year. Therefore the survivorship bias that is a large portion of that 33% will be smaller when we only consider December.

My apologies, I am trying to get this right with the data available to me. I believe I will be able to construct a better estimate for only the month of December. Will work on that today & write a new post as appropriate.