Health I.Q.: Is the Flu Shot a Must for Pregnant Women?

Flu season, which runs officially from October through May, is in full effect. And while, since 2012, the American College of Obstetricians and Gynecologists has recommended that pregnant women get the flu shot, some further reassurance is always appreciated. From the immunological impact on a fetus to mercury concerns, we asked Dr. Sarah Kilpatrick, chair of the Department of Obstetrics and Gynecology at Cedars-Sinai Medical Center in Los Angeles, to clarify some key points.

Q: Is the flu shot a must for pregnant women?

A: Any woman can decline any health care recommendation; however, the flu vaccine should be given the strongest recommendation to all pregnant women during flu season. Pregnant women seem to get sicker with the flu than nonpregnant women and have a higher rate of respiratory complications like pneumonia and a higher rate of death. As recently as 2009, with the H1N1 flu, a significant number of pregnant women died in the United States. When the mother gets really sick from the flu, particularly with pneumonia, her oxygen levels go down and this affects the fetus, which can become serious with the sickest mothers.

Q: Are there drawbacks to getting the flu shot during pregnancy?

A: None, as long as a woman isn’t allergic. Pregnant women should, however, only get the shot, which is inactivated flu vaccine. They should not get the nasal spray, which is live attenuated vaccine. They do not have to worry about thimerasol, which is the preservative in the multi-use vials and has an extremely tiny amount of mercury in it—far less than any amount in fish, for example. There is absolutely no evidence that it has any risk in this context. [Note: A mercury-free vaccine is available; ask your practitioner for more information.] And there is no evidence of risk to the fetus at any gestational age, so the benefits far outweigh any risks.

Q: Does the vaccine help arm a fetus against the flu after birth?

A: Yes. The antibodies from the vaccine cross to the fetus and then protect the neonate from getting the flu. The baby cannot get his or her own shot until at least six months of age, so this passive protection is really important for a newborn born during flu season.

Q: Are there any alternatives to the shot or other precautionary measures that mothers-to-be can take?

A: Really, no. Flu is extremely contagious. Even if one practices the best hand washing, it won’t fully protect you from others who do not.