A recent study shows that the usage of the Tdap vaccine on pregnant women is not linked with small birth sizes, an increased risk of preterm birth or maternal hypertensive disorders.
The vaccine is administered to women during pregnancy to protect their babies from pertussis. Pertussis is known as whopping cough. Only two vaccines are available for dealing with whopping cough. One of the two is DTaP, a vaccine available for younger children and the other one is Tdap, prescribed for everyone over 11 years old, including pregnant women.
A study regarding the effect of the Tdap vaccine was conducted by Dr. Elyse O. Kharbanda and her associates. Dr. Kharbanda is part of the HealthPartners Institute for Education and Research in Minneapolis.
For the study, the scientists used health records from 123,494 women found in the Vaccine Safety Datalink concerning pregnancies with live birth at two locations in California during a period of 3 years total. They analyzed the data to see if there are side effects linked to the usage of Tdap during the pregnancy of these women. 26,229 women were given the Tdap medicine during their pregnancy and 97,265 were not, although, 46% of the 97,265 women received Tdap before pregnancy.
The preterm birth rates were 6,3% in women exposed to the vaccine and 7,8% in those that were not. The rates of Small for Gestational Age infants were almost the same in the two study groups with 8,3% and 8,4%. The rates of maternal hypertensive disorders, including eclampsia, preeclampsia and hypertension were at 8,0% and 8,2%. The difference between the groups was not significant in all cases.
“Given limited prior safety data, continued widespread pertussis transmission, and current recommendations to routinely vaccinate during pregnancy, our study provides important information on the safety of Tdap vaccination during pregnancy”.
Said the authors of the study.
The Centers for Disease Control and Prevention funded the study published online in JAMA on November 11. Some of the associates of Dr. Kharbanda reported connections to Pfizer, Merck, MedImmune, Novartis, Nuron Biotech, Protein Science, Sanofi Pasteur and GlaxoSmithKline. Two of them are employees of CDC. Dr. Elyse Kharbanda reported not having any financial disclosures.