study pregnant women covid vaccine miscarraige

Answer: just remove most-likely-to-miscarry vaccinated women from the data!

Are COVID vaccines safe for women trying to become pregnant?

A newly published study that intended to prove that COVID vaccines are safe for women trying to become pregnant is raising more questions than it answers.

The study appears to intentionally exclude women most likely to experience miscarriage, but only among the vaccinated cohort!

This study is cited on Twitter by COVID vaccine promoters, who did not read it past the abstract, as the full text is not free.

tweet covid vaccine pregancy
© Lauren Berson Sugarman/X
I decided to spend $55 of my paid subscribers' contributions and purchased the full text of the study. I am glad I did - there is something to report to all of you!
reeipt study vaccine pregnancy
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Study Design

The study looked at a cohort of women actively trying to conceive naturally. What makes it interesting is that these women intentionally test for pregnancy much more frequently than women who are not "actively trying to conceive."

So, participants of this cohort know their pregnancy status by about Week 4. (Remember, gestational weeks (GW) are counted since day 1 of the last period).
design study vaccine pregnancy covid
In most situations, Week 4 (GW 4) is just before the next period, and women not trying to test for pregnancy would not yet know they are pregnant. Generally speaking, most women would get alerted by a "missing period" only by week six. However, miscarriages are most frequent in the early weeks of pregnancy, when many women are not even aware of being pregnant.

This is why the 25% miscarriage rate, which sounds higher than usually discussed, is at least partially explained by early pregnancy awareness.

This chart from the study shows when miscarriages happened to study participants.
miscarraige statistics
Study Results Intentionally Skewed by Removing Only Vaccinated High-Risk Women

On the surface - based on just the abstract - everything is straightforward. Rates of miscarriage among vaccinated and unvaccinated (before pregnancy) women were compared and adjusted for "propensity." Propensity adjustment makes some sense: for example, older women are more likely to miscarry and also more likely to be vaccinated. Effects of such factors could produce biased results, so authors adjust for "propensity scores."

Authors state:
The propensity score-weighted IRR comparing female participants who received at least one dose any time before conception versus those who had not been vaccinated was 0.85 (95% CI: 0.63, 1.14). COVID-19 vaccination was not associated with increased risk of either early miscarriage (GW: <8) or late miscarriage (GW: 8-19).
The problem with the above is that the authors performed a very strange data manipulation: they intentionally excluded some women from analysis in a way that seems very unfair: they excluded 75 vaccinated women, most likely to miscarry, for each similarly situated unvaccinated woman!!!

The paywalled supplement shows how such vaccinated women were removed:
study miscarraiges covid vaccine altered
© Human Reproduction
Stop here for a second, please: The authors "trimmed" only 0.1% of unvaccinated women, but removed a whopping 7.5% of vaccinated women, most likely to miscarry!

How is that fair for a comparison?

It is not fair at all as it skews the result and excludes numerous vaccinated miscarriages from analysis - allowing the authors to put their thumb on the scale of comparing vaccinated vs. unvaccinated outcomes.

Was the Data Fake?

Was there data faking involved?

The factors making women more likely to miscarry are age, smoking status, and so on.
miscarraige risks
© VeryWell

The factors making fertile women more likely to vaccinate are mostly "believing science" and trust in mainstream TV, and perhaps age.

How could it be that the ratio of "most likely to miscarry" favors vaccinated women 75:1? It is simply not believable to me.

I hope that someday, we will find out how the authors got this impossible 75:1 exclusion rate, removing seventy five "most-likely-to-miscarry" vaccinated women for every one such unvaccinated woman.

Unfortunately, the authors refuse to share the underlying data:
data vaccine study pregnancy hidden
© Yland et al.
COVID Vaccine Made Vaccinated Women MORE Likely to Get COVID

COVID vaccine advocates often point out the "protective effect of vaccines" for vaccinated pregnant women.

Sadly, in this study, vaccinated women were MORE likely to get COVID!
stody covid vaccine pregnancy
Vaccination DURING Pregnancy Increases the Risk of Miscarriage?

Take a look at the "miscarriage by week of gestation" chart. I highlighted the cumulative percentage of miscarriages occurring from Week 6:
study covid vaccine pregnancy
You can see that in this study, about 32% of all miscarriages occurred in Week 6 or after. As 25% of all pregnancies in the study ended in miscarriage, it means that approximately 32%*25% = 8% of pregnancies end in miscarriage during gestational week six or thereafter.

Remember that the women in the study we are discussing, were not selected for receiving vaccination during pregnancy. (even though some of them received vaccines, and the study is not specific on how many did)

How does the miscarriage rate for women who definitely were vaccinated during pregnancy compare?

The famous Zauche study of V-Safe data shows that V-Safe pregnancies where all pregnant mothers were vaccinated show a much higher 14.1% cumulative miscarriage rate from Week 6.
risk spontaneous abortion covid vaccine study

Does the Covid vaccine, given during pregnancy, increase the risk of miscarriage (starting from GW 6) from 8% to 14.1%? It seems like it! Unfortunately, we cannot answer that definitively, but the alarm signal is right here.

Here's another alarm signal for vaccination during pregnancy: Moderna, a higher-dose vaccine, has a 42% greater chance of miscarriage than lower-dose Pfizer:

There was never a Clinical Trial Among Pregnant Women

All of the above questions could be settled if our health authorities asked Pfizer and Moderna to contribute a small amount of their billion-dollar profit and conduct a randomized trial of pregnant women and future mothers trying to conceive. Had they done so, and had they been honest, we would know how dangerous COVID vaccines are for pregnancies.

Since these companies did not want to spend money on trials (or were afraid of the results becoming known), we will have to follow second-rate, biased studies, trying to decipher the data that is not even publicly available.

As the original Covid vaccines are not even given anymore, we will never know with certainty just how bad their effect was.

But one thing we know: honest studies do not exclude subjects at a 75:1 ratio to favor their preferred aim of the study.