From the outside, they looked like other recently built San Gabriel townhouses — two stories, Spanish style, with roofs of red tile.
Inside they were maternity centers for Chinese women willing to pay handsomely to travel here to give birth to American citizens.
Southern California has become a hub of so-called birthing tourism. Operators of such centers tend to try to blend in, attracting as little attention as possible.
But on quiet, residential Palm Avenue, neighbors had noticed an unusual number of pregnant women going in and out, and some complained about noise.
On March 8, code enforcement officials shut down three identical four-bedroom townhouses functioning as an unlicensed birthing center.
The homes, officials said, had been converted into maternity centers. Inside, they found about 10 mothers and seven newborns.
"The people were sitting and eating at a table. All the babies were in bassinets with a nurse attending to them," said Jennifer Davis, San Gabriel's director of community development.
The city fined the manager of the property, Dwight Chang of Arcadia, $800. He was cited for illegal construction and ordered to acquire permits and return the buildings to their original condition.
"They had moved walls around without proper permits. They did interior work that can sometimes create unsafe environments afterwards," Davis said. "And it's a business in a residential neighborhood. They are not permitted to operate there."
The Chinese mothers have since left the U.S. or moved into hotels, officials said. On Wednesday, construction work in the houses was underway. The doors were open, and visible inside was the detritus of a hasty departure — boxes of diapers, a baby-bottle sterilizer, a rice cooker, an electric kettle, bags of chopsticks and piles of Chinese-language magazines.
The garage of one of the buildings appeared to have been converted into an extra bedroom.
"It felt like something wasn't right in there," said Taylor Alderson, who was shocked to hear what had been going on next door. "There was a constant barrage of pregnant women going in and out of the house."
She said she rarely heard babies cry. But she was annoyed by the stream of traffic from visitors delivering baby products and the strong smell of "cheap canola oil" being used to stir fry vegetables.
"It's just too much to take in," Alderson said. "They count on people here being busy and keeping to themselves. In a more affluent neighborhood, they wouldn't' be able to get away with it."
An elderly neighbor who has lived on the block for 54 years said she did not want her name used because she feared retaliation. But she said one of the pregnant women once asked her where the local park was and if she could use her kitchen.
"She was unhappy with the food and the accommodation. They told her she had to eat what they cooked for her. I took her out to dinner," the woman said. "She even talked me into taking her to the hospital. She was having labor pains five minutes apart. Almost had the baby in my car."
The birthing centers are a twist on similar centers in China in which women recuperate for a month after delivery, following a strict diet and traditional rules meant to ensure their future health.
American centers offer these services as well — but the focus here is on giving birth. The actual deliveries take place in local hospitals. At birthing centers such as the one closed in San Gabriel, mothers get room and board and care before and after delivery.
It is not illegal for pregnant women to travel to the U.S. to give birth. Birthing centers advertise in wealthier Chinese cities, where some women can afford the thousands necessary to make the trip to America for a few months.
Most of the women go back to China after giving birth. But they know their children can return easily in the future to enjoy such benefits as free public education.
That bothers some of those living near the San Gabriel center.
"If they lived here, I don't mind," said Duke Trinh, who lives a few houses down. "If they are running a business, I don't want them here. It's not fair for us if [the mothers] go back to China and later send their kids here for education — because they don't pay taxes, we do."