Thread by @VikiLovesFACS

Over the last few days more people have asked me if the #COVID19 #vaccine reduces fertility. The short answer is still no. The long answer is... also no, but now with EVEN MORE DETAILS. The UK government guidance has also changed since I wrote my last thread. So, an UPDATE... 🧵

BUT FIRST... I have put together a short explainer about #COVID19 #vaccination, #fertility, #pregnancy and #breastfeeding. 2/19

You can find it here:

drive.google.com/file/d/1_wHIYX…

The original thread focussed on the molecular reasons we would not expect the COVID19 vaccine to reduce your chances of getting pregnant. 3/19

https://twitter.com/VikiLovesFACS/status/1339510379332988929?s=20

I also explained that if, as proposed, the immune response to the vaccine attacked the placenta, the immune response to the *virus* would do the same. And we don’t see that. 4/19

Papers:
link.springer.com/article/10.100…
ajog.org/article/S0002-…
link.springer.com/article/10.100…

Since I wrote the last thread, I have found more evidence to suggest that COVID19 vaccination will not reduce fertility. 5/19

First, although pregnant people were not included in the first round of trials, and participants were asked to avoid becoming pregnant, nonetheless about 20 became pregnant by accident. None of them have reported any problems with their pregnancies. 6/19

I have also found experiments in rats, who were given the vaccine while they were pregnant or before they were allowed to mate. There were no effects on fertility, pregnancy or the health of the babies. 7/19

You can read about these experiments here:

assets.publishing.service.gov.uk/government/upl…

Finally, the UK government updated their guidance on the 30th December. 8/19

You can find the new guidance here:

assets.publishing.service.gov.uk/government/upl…

Pregnant people were not included in the first round of trials, and participants were asked to avoid becoming pregnant, so the UK government initially advised that the same measures be followed for the wider use of the vaccine. 9/19

Not all governments took this approach: for example, the USA approved the vaccine in pregnancy from the outset. 10/19

Following the publication of the data showing that the vaccine is safe in pregnant animals on the 10th December, and pressure from pregnant workers on the frontline, who did not want to be denied protection against the virus, the government changed its advice. 11/19

The new advice says... 12/19

1. Those who are trying to become #pregnant do not need to avoid pregnancy after #COVID19 #vaccination. 13/19

2. There is no known risk associated with giving non-live vaccines whilst #breastfeeding. Breastfeeding women may be offered #vaccination with the Pfizer-BioNTech or AstraZeneca #COVID19 vaccines. 14/19

3. #Vaccination in #pregnancy should be considered where the risk of exposure to #COVID19 infection is high and cannot be avoided, or where the person has underlying conditions that put them at very high risk of serious complications of COVID19. 15/19

(But there is insufficient evidence to recommend routine use of COVID19 vaccines during pregnancy, ie. we are not yet going to vaccinate all pregnant people against COVID19, like we do for flu... 16/19

...Although given the increased risks of COVID19 in pregnancy, I think this is something that may well be considered in the future.) 17/19

A useful decision-making tool for pregnant people who have been offered the COVID19 vaccine is here. It also outlines the additional risks that people face if they catch COVID19 during pregnancy. 18/19

drive.google.com/file/d/1amyuWe…

I hope that this has answered some of the questions I am being regularly asked about this. Though I am busy, I think it is important to talk about this and spread the word about the new guidance, so I will try to reply as quickly as I can to any questions. \thread