For decades, China's family planning policy limited most urban couples to one child and rural couples to two if their first was a girl.
Couples who exceeded the limits were ordered to pay a social compensation fee. To pressure them into paying, some local authorities refused to register the child if they parents didn't pay up, which limits the child's access to education, health care and other benefits.
Some parents of unregistered children stood in a line outside the gates of the national family planning offices on Tuesday, holding banners with slogans including: "They are all our motherland's flowers and should not be treated differently."
One protester, Wan Changru, said the roughly 20 people included parents and grandparents of unregistered children and that they wanted family planning officials to cancel their fines.
Starting this year, all Chinese couples are allowed to have two children following an announced change to the 35-year-old policy in October.
"Now that every couple can have two children, all kids should be treated equally, no matter whether they were born before or after the policy change," said Wan, who is also taking family planning officials to court to try to get her 6-year-old daughter registered.
Wan and others have protested at local and national family planning commissions several times previously, but this was the first since the policy was relaxed.
On Tuesday, she said the security guard called police but no police came. "This is totally different to what happened before, as dozens of police would come to stop us in the past," she said.
The national family planning commission said in December that it had repeatedly ordered its local offices not to withhold registrations, and had carried out inspections to this end.
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