BEIJING (Reuters) - A sperm bank in Beijing has set strict criteria for would-be donors, including a requirement that they are loyal to China’s ruling Communist Party.

The state-run Peking University Third Hospital, according to a post on its Wechat account, has been seeking contributions from men with a “good political mindset” and “a love for socialism and the motherland”, who must also be “supportive of the leadership of the Party” and loyal to its work.

The post was edited on Friday, removing references to the Party. But it continued to say men aged 20-45 with “orthodox manners”, “good character” and no political problems or infectious diseases were encouraged to register to donate sperm by May 23.

Donors are entitled to up to 5,500 yuan ($870) in cash for their trouble, the posting said.

China’s birth rate is one of the lowest in the world and has become a concern for the government, which dropped its decades-old one-child policy in 2015.

Official encouragement to mate comes as the Communist Party tightens its grip in many aspects of society - from the economy to politics.

The Peking University Third Hospital could not be immediately reached for comment, outside of business hours on a public holiday.