The CDC’s Advisory Committee on Immunization Practices has reported a ‘definitive’ study that found no risk of miscarriage from the flu vaccine, according to

The new study matched 1,236 pairs of women: in each pair one of the women had miscarried between 6 and 19 weeks; the other woman, or control, had given birth.

For each flu season and even when all women and seasons were combined, there was no evidence of increased miscarriage risk after influenza vaccination during the first 28 days, the study found. There was also no significant association between miscarriage and influenza vaccination in the 29- to 56-day risk window and beyond.

“This is a very definitive study for a recent, relevant time period of flu and should remove all doubts a woman might have about whether it is safe to be vaccinated during pregnancy,” said co-investigator Dr. Edward Belongia, director of the Center for Clinical Epidemiology and Population Health at the Marshfield Clinic Research Institute in Wisconsin.