According to the US Immigration and Customs Enforcement (ICE) agency, the raids targeted apartment complexes in suburbs of Los Angeles including Irvine, Rowland Heights and Walnut, where foreign clients are thought to be housed.
"Such businesses provide travel and lodging services to pregnant foreign nationals interested in coming to the United States to give birth so their offspring will be American citizens," ICE spokeswoman Virginia Kice said.
She added that the raids' goal was to gather "further evidence related to a variety of possible criminal violations, including visa and tax fraud, money laundering, and conspiracy."
The so-called maternity hotels are mainly designed for Chinese women who are ready to pay from $15,000 to $50,000 for a spate of services, including lodging, transportation and food, as well as for social security numbers and US passports for their offspring.
The more expensive maternity tourism packages reportedly included recreational trips to Disneyland, shopping malls and even to a firing range.
Investigators said that the businesses, which are being advertised online and through social media, have names including "You Win USA Vacation Resort" and "USA Happy Baby Inc."
Meanwhile, Chinese state media outlets have reported that in 2012, nearly 10,000 Chinese women gave birth in the United States.
