The flu subgroup of the Joint Committee on Vaccination and Immunisation (JCVI) said the vaccine would help protect women and their unborn babies.
The subgroup said mothers-to-be should get the jab in their second and third trimesters if they are due to give birth during the flu season.
The move still has to get the agreement of JCVI leaders and then ministers.
The flu vaccine is currently offered to all over 65s and certain at risk groups such as people with diabetes and respiratory disease.
The experts also recommended extending the at risk group to people with degenerative diseases such as Alzheimer’s.
If the recommendations are ratified later this year, the vaccine will be made available in 2007.
In previous years there have been shortages of flu vaccine for those who are already eligible.
The subgroup, led by Simon Kroll, professor of paediatrics and infectious diseases at Imperial College, London, said: “The majority of published work showed that pregnant women are at higher risk of mortality and morbidity in influenza pandemic years.
“In addition to the risk of influenza infection to pregnant women, there may be potential benefits in maternal vaccination to the foetus or newborn.”
The sub group noted there was a risk of side-effects, but analysis in the US where pregnant women are given a flu vaccine showed this was small.
It recommended women who are over three months pregnant and due to give birth between November and March should get the jab.
Flu is estimated to kill several thousand people in the UK each year and affects 10 to 15% of the population each year.
Rosie Dodds, of the National Childbirth Trust, said: “Pregnant women are at greater risk of contracting infections because there immune system is compromised by being pregnant.
“But I think if this does happen the risks of side effects will need to be fully explained to women so they can make a choice as there are some vaccines pregnant women are advised not to have.”
A Department of Health spokesman said it was still awaiting the JCVI decision, which is expected later this year.