Calls are being made for more information about the safety of vaccinations for premature babies after twin brothers nearly died.
The Johnson family believed their problems were behind them
Niles and Harvey Johnson, who were born nine weeks prematurely, stopped breathing within hours of having their first vaccinations.
Their father, Tom, resuscitated them while his wife, Melanie, telephoned for an ambulance.
Although Niles and Harvey survived, their parents say they were not warned of the risks vaccines posed for premature babies.
Daventry and South Northamptonshire Primary Care Trust said the benefits of vaccines outweighed the risks, but it would be investigating the case.
The twins had their first injections at a GP surgery near their home in Long Buckby on 21 August just over a week after arriving home.
The first vaccinations are to immunise babies against whooping cough, diphtheria, tetanus, meningitis and polio.
Mr and Mrs Johnson said hours later their eight-week-old babies were rushed to hospital with breathing difficulties.
"We just went into a state of panic. You just don't expect to see your babies stop breathing," said Mrs Johnson.
"Thank goodness Tom was able to stimulate them while I was on the phone to the ambulance.
"We thought all the problems were all behind us - we thought when we came home we would be a happy family."
The twins will continue having jabs but will get them in hospital
She added: "It could have been a very different Saturday morning we were waking up to."
Mr and Mrs Johnson want more information given to parents of premature babies warning of the possible dangers of injections.
Daventry and South Northants Primary Care Trust said such side-effects were very rare.
The trust has arranged for the twins to have their next injections in hospital, where they will spend 48 hours under observation.