Atlanta ? Pregnant women should take prescription flu medicines if they are diagnosed with the new swine flu, health officials said Tuesday.

So far, the swine flu has not proven to be much more dangerous than seasonal influenza, and it’s not clear whether or not pregnant women catch swine flu more often than other people. But in general, flu poses added risks for pregnant women, said Dr. Anne Schuchat of the U.S. Centers for Disease Control and Prevention.

Pregnancy weakens a woman’s immune system so that she’s more likely to suffer pneumonia when she catches the flu. In earlier flu pandemics, infection also raised the risk of a premature birth, said Schuchat.

Pregnant women with asthma and some other health conditions are particularly at risk for complications.

CDC officials recommend Tamiflu for pregnant women.