False: Fifty-eight percent of pregnant women suffered a miscarriage in the Pfizer vaccine trials.

Context

Since being released, Pfizer's vaccine trial documents have repeatedly been misused and misinterpreted to promote claims that COVID-19 vaccines are unsafe, especially for pregnant women. 

The Facebook page of The Reclaim Party, a right-wing political party in the United Kingdom founded by British actor and political activist Laurence Fox, posted a video interview with Dr. Tina Peers, a consultant specializing in obstetrics and gynecology, on February 25, 2023, claiming that 58 percent of pregnant women suffered a miscarriage during the Pfizer vaccine trials. Elon Musk amplified the video on Twitter, and it has been viewed, shared, and commented upon extensively. 

Dr. Peers stated in the interview that 58 percent of pregnant women suffered a miscarriage during the Pfizer Vaccine studies. However, she has misquoted data from the EU Periodic Safety Update report. 

In Fact

Following the viral interview with Fox, Dr. Tina Peers justified her claim with a Tweet: "The data I quoted on the Laurence Fox show has just been updated February 23. Here is the latest version. Look at table 39 in particular although the whole article is worth reading," She then shared a link to the European website edition of the Children's Health Defense, a known anti-vaccine group.  

We accessed the Periodic Safety Update Report (PSUR #1), the original report on which the above article was supposedly based. The report covers Pfizer vaccine trial data from the six months between December 19, 2020, till June 18, 2021.

We found that the clinical trial data in the report states that there were 152 cases with 149 unique pregnancies. Of the 145 mother cases, 94 showed no clinical events, and 25 had non-serious events. On the other hand, 26 had serious events, of which 21 were miscarriages. Around 14 percent suffered miscarriages, according to the data in the report.

Table 39, seen in PSUR #1 and duplicated in the Children's Health Defense article evidenced in the claim, provides detailed data about the 26 serious event cases and is a subset of the main data shown in Table 38 in PSUR #1. The latter indicates that there were 149 pregnancies with information available. However, Peers has misrepresented the data in Table 39. It shows 15 miscarriages out of 26 pregnancies and arrives at 58 percent.

On February 27, 2023, Peers tweeted in reply to a repost of the video interview, admitting her mistake and stating that the miscarriage rate is double what we would expect but is still a tragedy. 

Further, data from the Phase 2 and 3 trials of Pfizer published by the FDA shows three miscarriages in 42 pregnant women given the vaccine, amounting to 7 percent. The placebo group showed a slightly higher number, 15 percent.

A press release from the U.S. Centers for Disease Control (CDC) published in August 2021 stated that an analysis of data from the v-safe pregnancy registry "did not find an increased risk of miscarriage among nearly 2,500 pregnant women who received an mRNA COVID-19 vaccine before 20 weeks of pregnancy." Further, it states, "Miscarriage typically occurs in about 11-16% of pregnancies, and this study found miscarriage rates after receiving a COVID-19 vaccine were around 13%, similar to the expected rate of miscarriage in the general population." The CDC, therefore, recommends that pregnant women get vaccinated against COVID-19, as the benefits outweigh any known or potential risks.

Logically and other fact-checking organizations have debunked similar claims resulting from flawed calculations, including that 44 percent of pregnant women suffered a miscarriage in the Pfizer COVID vaccine trials. Multiple studies have also shown that COVID-19 vaccination is safe during pregnancy. 

The Verdict

The claim that Pfizer trial documents show that 58 percent of pregnant women suffered a miscarriage during the trials is false, as the papers on which the claim is based clearly show that the percentage of miscarriages is much lower. The claim emerged from a miscalculation and misinterpretation of clinical trial data involving pregnancy outcomes in vaccinated women. Therefore, we have marked the claim as false.

The COVID-19 pandemic has given rise to a lot of potentially dangerous misinformation. For reliable advice on COVID-19, including symptoms, prevention, and available treatment, please refer to the World Health Organization or your national healthcare authority.