A growing number of Russian couples are visiting Korea to have babies through artificial insemination or other methods, but many of them are being turned back because they are not legally married.
Korean laws require the submission of marriage certificates or proof of family relations for fertility treatment.
But in Russia only about 60 percent of couples living together register their marriage, due to a socialist-era practice whereby unmarried women found it easier to get a job.
The situation is the same in Ukraine and Uzbekistan. Kim Gwang-rae at MizMedi Hospital in Seoul said, "Many Russian patients find it hard to understand the requirement for marriage certificates."
This has led to growing calls for the regulations to be revised. Critics of the law say stringent standards should not apply to medical tourists as long as there are no concerns for their personal safety or potential ethical breaches.
Last year, revenues from foreign medical tourists in Korea surpassed US$100 million, according to government statistics. And the number of infertility patients from abroad rose from 1,173 in 2010 to 2,505 in 2012. Ninety percent of them are from Russia or neighboring CIS states.
The number of Russian patients has risen more than five times over the last three years from 179 to 911. Not only is Korea relatively close, but the country's medical technology in treating infertility has a top-notch reputation.
Kim Sun-wook, an attorney specializing in medical malpractice, said, "A growing number of couples in Korea are opting not to register their marriage, and this requires more flexible regulations in terms of proof of marriage, be it for locals or foreigners."