The arrest of Tammy Davis-Charles, 49, comes weeks after Cambodia's government declared a ban on commercial surrogacy in the South-east Asian country which had attracted several dozen Australian couples seeking to become biological parents.

Ms Davis-Charles, the mother of twin boys through surrogacy in Thailand, was being held in the office of anti-trafficking police on Sunday and will be brought before a court in Phnom Penh on Monday, where she will face questioning.

Police Colonel Keo Thea, head of the Anti-Human Trafficking Office, told Fairfax Media that Ms Davis-Charles, who is from Melbourne, could face up to two years' jail if charged and convicted under Cambodia's penal code for allegedly engaging in surrogacy and allegedly falsifying documents.

"We found she has faked documents such as Cambodian birth certificates," he said.

Police have also detained a 28-year-old Cambodian nurse and 28-year-old male civil servant during a raid on a rented house in the western suburbs of Phnom Penh on Friday.

They seized two passports, money, mobile phones, a computer and documents.

Colonel Keo Thea said Ms Davis-Charles has arranged for more than 20 Cambodian women to carry babies through her Fertility Solutions PGD clinic.

"So far five or six children have been born over more than one year in Cambodia," he said.

Colonel Keo Thea said Ms Davis-Charles "contacted Cambodian girls for bearing pregnancies and she contacted her customers overseas to come here".

"Most were Australians but she also helped other nationalities. For one surrogacy operation she got paid $US50,000. She has her own network," he said.

Cambodia's Health Ministry issued a proclamation on October 24 banning commercial surrogacy which was distributed to about 50 surrogacy providers and brokers operating in Phnom Penh.

Sam Everingham, global director of the Australian consultancy Families Through Surrogacy, said at the time that "scores of Australians will be forced to abandon their embryos in Cambodia, along with the dreams of a family".

Phnom Penh emerged as a new hub for surrogacy services in Asia after commercial surrogacy was banned in Thailand, Nepal and India.

Health officials said the ban would stay in place until the government drafts a law protecting Cambodian women giving birth to the children of other parents.

Cambodia's current law states "the child who is born out of the mother's uterus is her child".

The Australian government's travel advisory smartraveller.gov.au warns the act of commercial surrogacy, or commissioning of commercial surrogacy, is illegal in Cambodia, with penalties including imprisonment and fines.

Ms Davis-Charles moved her surrogacy business from Thailand to Cambodia after Thailand's military government shut down surrogacy clinics in Bangkok in the wake of the Baby Gammy scandal in 2014.

Fertility Solutions PGD's website posted on November 4 that "there are a lot of rumours floating around at present about Cambodia closing down, even the local newspaper(s) are starting to report it. The government are reviewing laws. Honestly it could go either way."

The post added: "Please be warned do not sign up with anyone trying to push through!!!! As you will most likely be caught up in the end when the baby is born, which becomes a nightmare."

On May 27 the clinic posted: "We are able to help all families types … there is no discrimination. We have helped many and have 90 per cent plus success rate."

Among testimonials thanking Ms Davis-Charles for her services in Bangkok and Phnom Penh were "Kate and David", who said she arranged for them and their egg donor to go to Cambodia for IVF treatment.

"All we knew of Cambodia was orphanages and land mines. What an experience we had in store … we thoroughly enjoyed our Cambodian experience and despite initial reservations, we wouldn't hesitate to recommend other families to have their fertility treatment" in Cambodia, the couple said.

Ms Davis-Charles wrote on the website that she at first starting helping couples wanting surrogacy services while she was a full-time nurse and her husband Simon was a stay-at-home father, caring for their twins.

But she says surrogacy inquiries "started to take over our life, as so many couples needed help and guidance through their journey".

"So we decided to move to Thailand and start a surrogacy business full-time, so I can help people all day everyday," she said. "This is the most rewarding and fulfilling job I could ask for. I'm once again blessed ... dreams do come true."