Covid-19: Study provides further evidence that mRNA vaccines are safe in pregnancy
BMJ 2022; 378 doi: https://doi.org/10.1136/bmj.o2013 (Published 12 August 2022) Cite this as: BMJ 2022;378:o2013
All rapid responses
Rapid responses are electronic comments to the editor. They enable our users to debate issues raised in articles published on bmj.com. A rapid response is first posted online. If you need the URL (web address) of an individual response, simply click on the response headline and copy the URL from the browser window. A proportion of responses will, after editing, be published online and in the print journal as letters, which are indexed in PubMed. Rapid responses are not indexed in PubMed and they are not journal articles. The BMJ reserves the right to remove responses which are being wilfully misrepresented as published articles or when it is brought to our attention that a response spreads misinformation.
From March 2022, the word limit for rapid responses will be 600 words not including references and author details. We will no longer post responses that exceed this limit.
The word limit for letters selected from posted responses remains 300 words.
Dear Editor
My recollection of embryology is that female babies are born with all their oocytes "ready to go", and that those oocytes are formed between three and four months of gestation.
Supposing a woman is vaccinated or takes drug X between 3 and 4 months of her pregnancy, could that vaccine/drug affect the oocytes which are developing at that stage?
Such an effect might only become evident when that child has children herself, which could be 15-40 years later.
I have not been able to find an answer to this question and hope readers might be able to confirm or refute my concern.
Competing interests: No competing interests
Dear Editor,
I was a little surprised that the first comparison should be between vaccinated pregnant and unvaccinated non pregnant, considering the study is about safety in pregnancy. There was no comparison of significant health events in the vaccinated pregnant (7.3%), against the unvaccinated pregnant (3.2%).
Almost every significant, severe, and serious health event comparison was lower in the unvaccinated pregnant.
Miscarriage or stillbirth was the most frequently reported adverse pregnancy outcome. Similar rates of 2.1% in the unvaccinated pregnant, and 1.5% in the vaccinated pregnant. There was no mention of the 175 (5.6% of 3114) other pregnant individuals, who reported experiencing miscarriage or stillbirth, the exact timings of these events relative to vaccination not having been collected, so not included.
I fail to see how this study shows vaccine safety in pregnancy and would hope there will be further studies on this subject.
Douglas R Hendrie
Competing interests: No competing interests
Dear Editor
It is interesting that another study is concluding the mRNA vaccinations to be safe in pregnancy, yet Pfizer themselves are not willing to make that claim. Pfizer state:
“Available data on Pfizer-BioNTech COVID-19 Vaccine administered to pregnant women are insufficient to inform vaccine-associated risks in pregnancy.” (1)
Who will be taking medico-legal responsibility for adverse reactions in these pregnant women or babies? Doctors and nurses who are vaccinating? Clearly, it won’t be Pfizer.
For further discussion points see my previous response (2).
(1) https://www.pfizer.com/news/press-release/press-release-detail/pfizer-an...
Competing interests: No competing interests
Dear Editor
May I gently take Jacqui Wise to task for her reporting of the Canadian study providing “further evidence that mRNA vaccines are safe in pregnancy”?
This seems to be a follow-on article to a January BMJ news item that she references “Covid-19: Vaccination during pregnancy is safe, finds large US study”.
Had she read the response to that article from GP Dr Ayiesha Malik (1), she might have chosen her words differently. Neither of these studies shows that mRNA vaccines are safe in pregnancy. They may, as Dr Malik pointed out, suggest that they are not known to be harmful.
To put the Canadian study in perspective, it looked at adverse events occurring in the seven days after immunisation, i.e. 2.5% of the duration of a pregnancy.
Ref
1) https://www.bmj.com/content/376/bmj.o27/rapid-responses
Competing interests: No competing interests
Re: Covid-19: Study provides further evidence that mRNA vaccines are safe in pregnancy
Dear Editor
Further to my recent response, it would appear the UK Government are now saying singing a different tune.
Under the heading “Toxicity conclusions.”
“In the context of supply under Regulation 174, it is considered that sufficient reassurance of safe use of the vaccine in pregnant women cannot be provided at the present time: however, use in women of childbearing potential could be supported provided healthcare professionals are advised to rule out known or suspected pregnancy prior to vaccination. Women who are breastfeeding should also not be vaccinated.”
https://www.gov.uk/government/publications/regulatory-approval-of-pfizer...
Douglas R Hendrie
Competing interests: No competing interests