A pregnant mainlander was sentenced to six months in jail yesterday for staying in the airport's restricted area without a permit.

Xie Miaoling, 26, had arrived from an overseas trip on July 14 and was due to board a flight to Guangzhou at 8.20pm that day.

However, she neither boarded the flight or arranged for any other flight out of Hong Kong, staying in the restricted area until July 21, when she started to have labor pains and asked to be taken to hospital.

In mitigation, Xie said she did not board the aircraft because she was feeling unwell.

The magistrate was not convinced, saying Xie deliberately remained at the airport as she wanted to give birth in Hong Kong.

Xie, who was bailed, pleaded guilty to one count of remaining in a restricted area without a permit when she appeared in a Tsuen Wan Magistrates' Court.

The court was told Xie remained in the restricted area of Hong Kong International Airport after she arrived.

She neither approached airline staff to arrange another flight ticket after missing her flight, nor ask airport staff for assistance.

On July 21, Xie started to have labor pains and called for medical help.

Lawmaker Leung Ka-lau said such behavior was dangerous as the mother-to-be did not have any body checks before giving birth.

``Both the mother and the baby were at risk as the hospital may not have enough time to make any preparations. They could suffer from complications,'' he said.

Leung said the number of mainlanders giving birth in Hong Kong has reached a low since public hospitals stopped accepting non-locals from April 2012.

Barrister Albert Luk Wai- hung said the incident indicated airport security measures should be raised to prevent a repetition.

But Luk said it is hard for airline staff to determine if passengers are pregnant when they hide it intentionally.