The Los Angeles County Board of Supervisors is reportedly reviewing tougher regulations to prevent foreigners from giving birth in the U.S. so their babies automatically get U.S. citizenship, CBS reported on Tuesday.

"Supervisor Don Knabe called for more rigorous zoning restrictions targeting boarding houses countywide where many Asian women reportedly obtain tourist visas and pay up to $15,000 so their children are automatically granted citizenship," the network said.

Most of the mothers who come to take advantage of the U.S.' quaint territorial principle are Chinese, but there are considerable numbers of Koreans as well.

Many Korean parents decided to give birth in these "maternity hotels" in the U.S. in order to give their babies the option of evading compulsory military service and receiving a cheaper education in the U.S.

CBS said the usual cost of having babies in these maternity hotels is US$30 000.

There are countless numbers of these hotels. "Knabe is also seeking to establish multi-agency inspection teams and funding to assist the inspectors with additional staff as well as Mandarin and Cantonese translators," CBS said.

It quoted Knabe as saying, "That's a cash cow for these folk. There's no tracing of records, these women are paying $30,000 to come over here to have a baby so it becomes a U.S. citizen, so at some point they can come back for an education here in the country, so that's another immigration issue."

CBS added that maternity hotels are thriving not only in Los Angeles but also in New York and elsewhere.