Most pregnant women in Sussex are not having a flu jab, new figures reveal.
Just a third of expectant mothers across Sussex have taken up the offer of the vaccine this winter.
Experts warn there is strong evidence pregnant woman have an increased risk of developing complications if they get flu, which can harm themselves and their child.
These include bronchitis and pneumonia and the increased chance of miscarriage.
Babies can also be born too early or have a low birth weight.
Nick Kendall, screening and immunisation manager for NHS England in Sussex, said: “All pregnant mums should make every effort to have the flu vaccination during their pregnancy.
“Complications are reduced by having a simple vaccination and I would urge all pregnant ladies to contact their local GP surgery and make an appointment as soon as possible.
“The vaccine can be given at any stage of pregnancy - it's safe for mother and baby, and is available until the end of March.
“It's free and will offer protection to you and your baby.”
Free flu vaccines are available every winter to pensioners and at-risk groups including people with long term health problems such as chest or heart problems.
Two and three-year-olds are also eligible for the free vaccine for the first time this winter.