The Itar-Tass news agency said the baby girl, named Maria, was born last month after her parents decided to keep the pregnancy secret for fear of being forced to move away from what is still a highly radioactive zone.
The baby was delivered by her father; doctors say she is in good health. The zone around the Chernobyl power plant was evacuated after the accident; most of the people who have since returned to live there are elderly.
From the newsroom of the BBC World Service
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