Amy Abolins, who is five months pregnant, was on her way to celebrate her 21st birthday at a bowling alley when the three-car family convoy, including her pregnant sister Zoe, crashed into each other on Hayling Island.

Amy, of Palmerston Road, Hayling, said: "The first thing I can remember is everyone braking and me going into the back of my older sister Kirsty.

The worried mum-to-be felt sharp pains immediately and she drifted in and out of consciousness because of the shock.

She said: "I had these horrible pains in my belly and I was absolutely petrified for the baby.

"I was so scared but the paramedics and the air ambulance pilots who came to help were phenomenal.

"They were absolutely amazing and I cannot thank them enough."

Miss Abolins, Island kept blacking out after the paramedics arrived so they radioed for help from the Hampshire and Isle of Wight Air Ambulance.

The crew tried to land in a nearby field but Miss Abolins was too ill to walk the short distance.

It was forced to land at the junction of Havant Road and Avenue Road instead, leaving the pilot with a very tricky maneouvre to touch down between two sets of telephone lines.

When the crew and paramedics discovered it was Miss Abolins' birthday they all sang Happy Birthday to keep her awake and calm.

Her sister Kirsty Rogers, aged 27, from Devon paid tribute to the courage of the pilot.

She said: "He landed the helicopter with such precision it was unbelievable. There was just a yard either side of the blades. What they did for my sister was fantastic."

Miss Abolins and her 19-year-old sister Zoe were both taken to Queen Alexandra Hospital, Cosham, and their unborn babies were given the all-clear. Zoe suffered whiplash and a sprained wrist.

Two cars had collided on the same stretch of read earlier in the morning, but no one was hurt.