Botox injections is arguably the safest and most effective preventive treatment for migraine headaches. There have been cases of pregnant women receiving Botox for various medical and cosmetic reasons, and no evidence suggests that the fetus gets harmed during this treatment. The botulinum toxin molecule is too large to cross the placenta and enter the circulation of the fetus, which further supports its safety during pregnancy.

An analysis of pregnancy outcomes after onabotulinumtoxinA exposure over a 29-year period was conducted to gain more insights into the safety of the treatment during pregnancy. The researchers examined data from the Allergan Global Safety Database from 1990 to 2018, focusing on pregnant women or those who became pregnant within three months of receiving onabotulinumtoxinA treatment. They analyzed the outcomes of these pregnancies to estimate the prevalence of birth defects in live births.

Out of 913 pregnancies, the study considered 397 with known outcomes. The majority of the mothers were 35 years or older, and most of the onabotulinumtoxinA exposures occurred before conception or during the first trimester of pregnancy. Among the 197 fetuses from 195 pregnancies, there were 152 live births and 45 fetal losses (including spontaneous and elective abortions). Four of the 152 live births had abnormal outcomes, with one major birth defect, two minor fetal defects, and one birth complication. The overall prevalence of fetal defects in live births was 2.6%, with a prevalence of 0.7% for major defects, similar to the rates seen in the general population. Among the cases with known exposure times, one birth defect occurred with preconception exposure and two with first-trimester exposure.

While the study has some limitations due to the nature of the data collected, the results indicate that the rate of major birth defects in live births exposed to onabotulinumtoxinA is consistent with the rates seen in the general population. However, it is important to note that there is limited data available for exposure during the second and third trimesters of pregnancy. Nevertheless, this updated and expanded analysis provides valuable real-world evidence for healthcare providers and their patients when considering Botox treatment during pregnancy.

I’ve treated more than a dozen pregnant women in my 30 years of using Botox for migraines. Some of them received Botox during more than one pregnancy. Some pregnant women sought Botox treatment specifically because they preferred to avoid taking any medications during pregnancy. Their decision was justified. When it comes to migraine drugs, including over-the-counter pain medications, they carry a higher likelihood of causing harm during pregnancy.