(CNN) - The flu vaccine reduces a pregnant woman’s risk of hospitalization due to influenza by an average of 40 percent, according to the Centers for Disease Control and Prevention.
The CDC analyzed data from more than 2 million pregnant women over six flu seasons and found that a flu shot significantly reduces a pregnant women's chance of being hospitalized for a flu-related illness.
Researchers found that more than 80 percent of pregnancies overlap with flu season.
The flu vaccine was equally protective for pregnant women during all three trimesters even with underlying medical problems like asthma and diabetes.
Health authorities say pregnant women can get vaccinated at any time.
The CDC says an estimated 80,000 Americans died of flu and its complications last winter.
Making it the deadliest season in more than four decades.