File picture: Spending two hours in her car seat is thought to have caused such oxygen deprivation that when Harper was taken out and laid down the sudden increase sent her body into shock.

London - A mother whose newborn began foaming at the mouth after a two-hour car journey warned parents not to leave babies in child seats for too long.

Kirsti Clark, 28, and husband Christopher, 29, became stuck in rush-hour traffic with three-week-old daughter Harper and sister Malena.

When they finally got home they took Harper inside but left her in the Maxi-Cosi CabrioFix car seat for 15 minutes while they put three-year-old Malena to bed. They then got Harper out and put her on a playmat at their home in Falkirk, Scotland. 

But Mrs Clark, a journalist, spotted that the baby's lips were blue. She said: "I could tell straight away that something was wrong." She blew gently into Harper's face to rouse her, then "white foam" started coming out of her nose and mouth. 

Mrs Clark added: "We both knew we needed to get her straight to hospital. My husband kept asking if she was breathing and I just had to say 'I don't know'. The whole way there all I could think was 'We are going to lose her'. 

"The doctors took her into resuscitation. By the time I got in there they had managed to get her breathing again. Seeing her like that was the worst feeling." The baby spent the night in hospital where doctors carried out blood tests and an ECG. They also examined the car seat. 

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Harper had suffered a seizure but there was no long-term damage. While doctors found her car seat was completely safe, they advised the family not to let her spend more than an hour in it at a time. It comes after a study found the angle of child-seat cushions can cause newborns' heads to flop forwards due to their weak neck muscles, potentially resulting in suffocation. 

Spending two hours in her car seat is thought to have caused such oxygen deprivation that when Harper was taken out and laid down the sudden increase sent her body into shock.

The authors stressed that while babies were safest in properly-fitted car seats, an adult should preferably sit next to them to check their breathing. 

Daily Mail