Swine Flu and Pregnancy

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Pregnant women are more likely to be hospitalized and are at higher risk of death and complications from flu, including swine flu and seasonal flu, than the general population. As scary as that sounds, experts say that most pregnant women who become ill with H1N1 swine flu will not have a serious problem. If you are pregnant, here's what you need to know.

Why are pregnant women at higher risk from swine flu?

Experts aren't entirely sure, but they surmise that as the fetus develops and grows there’s more pressure on the mother’s breathing and lung function, increasing the risk of her developing secondary infections such as pneumonia. Most of the maternal deaths from swine flu occurred in the third trimester.

Also, there are changes that happen to a woman's immune system while she is pregnant that can make her more susceptible to infections such as flu.

Will pregnant women be allowed to take the swine flu vaccine when it is available?

Yes. Pregnant women fall under a “high risk” category, according to CDC guidelines. A vaccine advisory committee recommended that pregnant women and those caring for and living with infants be among the first in line for the vaccine.

Until the vaccine is available, what is the best way for someone who is pregnant to prevent swine flu?

“I am recommending that my patients avoid contact with anyone who has flu-like symptoms, including fever, muscle aches, and upper respiratory symptoms. I’m also telling my patients to be cautious around anyone whose close contacts have similar symptoms, especially children,” says Rebecca Yee, MD, an ob-gyn in San Francisco. Pregnant women should wash their hands frequently and avoid touching their eyes, nose, and mouth. They should avoid crowded settings in communities with swine flu outbreaks.

If a pregnant woman gets swine flu, what is the best course of treatment?

She should take antiviral medication with suspected or confirmed flu as soon as possible, according to the CDC. Antiviral medication (Relenza, Tamiflu) can be taken at anytime during pregnancy.

If a pregnant woman or woman who is up to two weeks after delivery or pregnancy loss has had close contact with someone with flu, she should be considered for treatment with antiviral medication. The CDC defines close contact as caring for or living with a person who has confirmed, probable, or suspected influenza, or having high likelihood of exposure to respiratory or bodily fluids from this person.


Could these medications cause harm to her unborn baby?

Some adverse effects have been reported in pregnant animals given Tamiflu, but no relation between the use of the drug and adverse events in pregnant women has been established.

“The risk of complications from untreated influenza greatly outweighs any of the theoretical risks related to taking either Tamiflu or Relenza,” says Mark Phillippe, MD, MHCM, professor and chairman of the department of obstetrics, gynecology, and reproductive sciences at the University of Vermont College of Medicine.

Can a pregnant woman pass swine flu to her unborn baby?

“During severe infections with pandemic strains of influenza, it’s possible that the virus could infect the placenta, which carries blood to the fetus,” says Phillippe. While its to soon to know much about how swine flu affects a fetus, women with swine flu do seem to be at a higher risk for premature delivery. In past pandemics, pregnant women with flu had higher rates of stillbirth, spontaneous abortion, and premature birth.

Also, flu comes with fever. Studies have shown that a fever during the first trimester doubles the risk of neural tube defects and may be associated with other adverse outcomes. The risk for birth defects associated with fever may be mitigated by the use of anti-fever medications and/or a multivitamin that contains folic acid, but data are limited.

What happens if a woman comes down with swine flu right before her baby is born, or when the baby is a newborn?

She should deliver the baby at a hospital that is prepared for this type of delivery. A surgical mask should be placed on the ill mother during labor and delivery, and she should consider avoiding close contact with her infant until she has received antiviral medications for 48 hours and her fever has fully resolved. This will reduce, but not eliminate, the risk of transmitting H1N1 to the infant.

Infants are thought to be at higher risk for severe illness if they get swine flu, and very little is known about prevention in infants. If possible, only adults who are well should care for infants, including feedings.

If she gets sick after the delivery, her newborn should be cared for by someone who is well, until she feels better and for at least seven days after the onset of her symptoms. She may begin breastfeeding (or if not able to breastfeed, bottle feeding), and should wear a face mask.


Can a new mom with swine flu breastfeed her baby?

Breastfeeding is an option if a sick mother has recovered enough from the virus. The risk for transmission of the virus through breast milk is unknown but is probably rare. Actively infected women who are able to express their milk for bottle feedings should let a healthy family member take over feedings. If the mother is taking an antiviral medication, she can still breastfeed. But she needs to be on the antiviral medication for at least 48 hours beforehand.

WebMD Feature Reviewed by Louise Chang, MD on August 10, 2010




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