The Claim:
On his internet show, Del Bigtree claims that the Tdap vaccine given during pregnancy may be linked to stillbirth, preterm birth, and fetal death.
The Facts:
The study Del Bigtree refers to looked at reports in a government database called VAERS.
VAERS allows doctors, patients, or family members to report health problems that happen after vaccination. These reports do not prove the vaccine caused the problem. They only show that the event happened sometime after vaccination.
In the database, some pregnancy-related outcomes were reported more often than expected. But the study explains that VAERS data cannot show cause and effect because reports are voluntary and not verified the same way as in controlled studies.
The authors also note that the large numbers mentioned in the video come from a statistic called a reporting odds ratio. This number compares how often something is reported for one vaccine versus others in the database. It does not measure real-world risk or show that the vaccine caused the problem. If an event is rare, even a small number of reports can make the ratio look very large. The number can also change depending on how often people choose to report certain events. Because of this, reporting odds ratios are mainly used to flag issues that may need more study, not to show that a vaccine is dangerous.
Stronger research has not found a higher risk of stillbirth or fetal death from the Tdap vaccine during pregnancy. This research includes large studies that follow many people and compare what happens to those who got the vaccine and those who did not. Because these studies include many people and track real pregnancies, they are better at spotting rare problems like stillbirth or fetal death.
The Tdap vaccine is given during pregnancy because whooping cough, or pertussis, is dangerous to new babies. Before the vaccine, up to 9,000 children died from pertussis each year. Now, these deaths are rare enough to make news, but still preventable.