2009 H1N1 Flu (Swine Flu)
Information for Healthcare Professionals
What are the current recommendations regarding vaccination of pregnant women with the H1N1 vaccine?
The CDC’s Advisory Committee on Immunization Practices (ACIP) considers pregnant women or women who may become pregnant during flu season a high priority special population to receive the H1N1 monovalent vaccine as soon as it becomes available in October or November.
Is it necessary to have a PCR-confirmed positive test for H1N1 infection before treating pregnant patients who present with flu symptoms?
No. Treatment with antivirals should be initiated as early as possible because studies show that treatment initiated within 48 hours of illness onset is more beneficial. Treatment should not wait for laboratory confirmation of influenza because laboratory testing can delay treatment and because a negative rapid test for influenza does not rule out influenza.
Which antivirals should pregnant women with suspected or confirmed H1N1 infection be treated with?
Oseltamivir is currently preferred over zanamivir for treatment of pregnant women with suspected or confirmed influenza because of its systemic absorption. Oseltamivir can be taken during any trimester of pregnancy. The duration of antiviral treatment is 5 days. Although there are limited human data on the safety of oseltamivir and zanamivir during pregnancy and breastfeeding, the data that exist do not suggest a risk. In addition to use of antiviral medication, maternal fever associated with influenza infection should be treated with acetaminophen to avoid prolonged fetal exposure to high maternal high body temperature, which is associated with increased risks to the fetus.
Can pregnant women receive both the seasonal flu vaccine and the H1N1 vaccine?
Yes. The ACIP recommends that pregnant women receive the seasonal influenza vaccine in addition to the H1N1 vaccine as both vaccines are required to provide comprehensive protection against illness.
Can pregnant women receive the H1N1 vaccine if they are in their first trimester?
Yes. Given that pregnant women are at an increased risk for complications resulting from infection with the H1N1 virus, the ACIP recommends vaccination with the H1N1 vaccine for all women who are pregnant regardless of trimester.
Can pregnant women receive the seasonal flu vaccine and the H1N1vaccine at simultaneously?
Yes. The ACIP recommends that pregnant women receive both the seasonal flu vaccine and the H1N1 vaccine. As long as the different anatomic sites are used to administer the vaccines, the ACIP indicates that inactivated H1N1 and seasonal vaccines can be given at the same time. Pregnant women who have had an influenza-like illness in the past year are still encouraged to receive both the seasonal and H1N1 vaccines.
Is the H1N1 vaccine a “new” vaccine?
No. The H1N1 vaccine is a monovalent influenza vaccine similar to the regular seasonal flu vaccine. No new technology is being employed in the manufacture of the vaccine and there is nothing experimental about its preparation. In the future, the H1N1 virus will be incorporated into the seasonal flu vaccine and thus will eliminate the need for two different influenza vaccinations.
Can pregnant women receive FluMist?
Pregnant women are not advised to use the nasal spray form of the seasonal or H1N1 vaccines (FluMist), as both forms of this vaccine contain live attenuated virus.
Will the H1N1 vaccine contain thimerosal?
It is expected that both thimerosal-containing (multi-dose vials) and thimerosal-free (single-dose syringe) H1N1 vaccine products will be available in the fall. There is no evidence that thimerosal poses a risk to the fetus. However, for those who wish to avoid exposure to this preservative, both the seasonal and H1N1 vaccines will be available in thimerosal-free formulations.
If a pregnant woman has already had an influenza-like illness (before or during her pregnancy), does she still need to receive the seasonal flu vaccine and the H1N1 vaccine?
Yes. Pregnant women who have had an influenza-like illness in the past year are still encouraged to receive both the seasonal and H1N1 vaccines.
Should pregnant women presenting with flu-like symptoms be treated with antivirals even if it has been longer than 48 hours since symptom onset?
Yes. Though treatment should be initiated as early as possible it is still recommended that pregnant women with suspected H1N1 infection be treated, preferably with oseltamivir, even if it has been more than 48 hours since symptom onset.
How do providers get H1N1 vaccine for their patients?
Novel H1N1 vaccine will be procured and purchased by the federal government and made available for vaccinators at no cost. Shipping of the vaccine is expected to begin mid-October. Vaccines will be distributed to each state and allocated in proportion to its population.
To order the vaccine for California vaccinators: http://calpanflu.org/
For more information about H1N1
In California, contact 800-532-3749
Visit the Center for Disease Control H1N1 Flu Clinical and Public Health Guidance website
Download the H1N1 Flu (Swine Flu) , H1N1 Flu Vaccine, Seasonal Influenza and Vaccine duing Pregnancy and the Antiviral Medications to Treat/Prevent Influenza (Flu) and Pregnancy Factsheets for your patients
For residents outside of California but in the US or Canada:
Contact the Organization of Teratology Information Services 
For residents outside the United States or Canada:
Contact the European Network of Teratology Information Services.