As of the 13th September, the registry contained 5096 participants. 2/
After they have joined, the participants are interviewed in every trimester, shortly after giving birth, and again when their babies are more than three months old. 3/
First, they go through the data showing that, among 2456 people vaccinated before 20 weeks, the risk of miscarriage was normal.
This has been recently published and you can read about it in more detail here... 4/
But there is one additional graphic that is quite nice. This compares the week-by-week miscarriage rate in those who received the COVID vaccine, vs two studies of miscarriage rates from before the pandemic.
You can see that post-vax miscarriage rates are bang in the middle. 5/
The next section looks at outcomes for babies at birth.
The registry contains 1634 live born babies. 70% born following 3rd trimester vaccination and 30% following second trimester vaccination. 6/
Among these babies, the rates of preterm birth, being small for gestational age, admission to neonatal intensive care and infant death are all normal. 7/
45 babies had a birth defect. The types and rates of birth defects were consistent with what is usually seen in the USA. So no evidence of an increased risk of birth defects following vaccination in this cohort. 8/
That's all from the V-safe pregnancy registry! I'm off to do the school run now, but I'll be back later with an update from the Vaccine Safety Datalink... 9/9
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The authors looked at user data entered from March - September 2019 (pre-pandemic) compared to March - September 2020 (Pandemic). They also asked users to rate their stress levels (retrospectively) in the pre-pandemic and pandemic periods. 2/
The average cycle length decreased from 29.4 to 29.q6 days, and the average period of menstruation increased from 4.21 to 4.23 days.
Neither of these changes is clinically significant. 3/
People who are breastfeeding can sometimes get forgotten in the focus on pregnancy. But your questions matter too! And I particularly want to make space to address those questions because a lot of people have contacted me, worried about one particular blog post... 2/
I'll get to that later. But let's start by saying that @RCObsGyn and @MidwivesRCM recommend the COVID vaccine if you are breastfeeding. 3/
But why would anyone even think that such a thing might happen? Is it even worth researching?
The rumours that COVID19 vaccines would impact fertility were started by a vaccine skeptic who proposed that this might occur, so this is something that a lot of ppl may have heard. 2/
People who work in this area never thought this was very likely, for a number of reasons.
Not least, if this did happen COVID 🦠 would be associated with infertility or problems in early pregnancy, and luckily we don’t see that. 3/
Let’s start by looking at the effects at birth. We now have eight large datasets from four countries looking at almost 79,000 people vaccinated in pregnancy. The outcomes for the babies are all normal. 2/
(The CDC has recently put out data from 2 more US studies, bringing the total to 10. But there is some overlap between the participants in these studies and the ones quoted above, so I didn't add those in as unique participants.)
Why is effectiveness vs hospitalisation lower than against all infection? This is the opposite of what we see in larger studies of the whole population, eg. this PHE data… 2/