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Focus for Health: Several studies have concluded that activation of the maternal immune response adversely affects fetal brain development. [Knuessel 2014, Konat 2015, Tsukada 2015, Weir 2015, Baumann 2014, Cordeiro 2015, Giovanoli 2015]

CDC: +Focus for Health Foundation All vaccines activate the immune response because this is how they work to protect people against diseases. CDC and researchers from around the world have conducted several studies to assess the safety of whooping cough vaccine in pregnant women and their babies. The findings of these studies have shown no negative effects on the babies and support the safety and benefits of Tdap vaccination during pregnancy: ● Moro et al. Human Vaccines & Immunotherapeutics, 2015 http://www.ncbi.nlm.nih.gov/pubmed/26378718 ● Sukumaran et al. Obstet Gynecol, 2015 http://www.ncbi.nlm.nih.gov/pubmed/26444109
● Sukumaran et al. JAMA, 2015 http://www.ncbi.nlm.nih.gov/pubmed/26501534 ● Dabrera G, et al. Clin Infect Dis, 2015 http://dx.doi.org/10.1093/cid/ciu821.

Focus for Health: +Centers for Disease Control and Prevention (CDC) Thanks for your response. Are there any active studies performed on pregnant women or any studies showing long term neurological outcomes for the Tdap vaccine? We only know of VAERS which is passive and the reactions are known to be under reported and others that only look at immediate negative effects such as miscarriage. Also, isn't the Tdap vaccine a Class C drug? Class C drugs according to the FDA are drugs in which "Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks."