Chinese police are investigating a report of attempted baby trafficking on an internet auction site, according to a state-owned newspaper.
There is a thriving black market in babies in China
The advertisement was reportedly placed on eBay's Chinese website, Eachnet.
Boys were advertised for 28,000 yuan ($3,450) while girls were offered for 13,000 yuan ($1,603), Eachnet manager Tang Lei told the China Daily.
The offer could have been a hoax, but it comes as baby trafficking is seen as an increasing problem in China.
China's strict "one child" birth control policy, coupled with the traditional bias for male children, has led to widespread reports of child abductions, and several people have been sentenced to death for their part in smuggling rings.
According to Eachnet, the advertisement was registered in Shanghai on 16 October.
The seller, under the user name "Chuangxinzhe Yongyuan" or "innovator forever", said the babies would be available within 100 days of their birth.
The seller said the service was being provided for the benefit of China's millions of infertile couples.
All the children were described as coming from Henan province in central China.
Although no deals were struck, more than 50 people browsed the listing before it was removed, including one who left an enquiry.
According to Tang Lei, the website automatically screens all the postings it receives. But the word "baby" is not seen as a forbidden term because so many baby products are advertised on the site.
Mr Tang admitted the posting may have been a hoax - but he added that, if not, the person responsible for the attempted sale could face many years in prison or even the death penalty.