News of an imminent event - fuelled by rumours in Germany - was wild speculation, her keeper, Mick Carman, said when it became clear that the increased hormone activity picked up in Ming Ming's urine may be due to a phantom pregnancy.
Mr Carman said artificial insemination in March with sperm from Bao Bao, Berlin Zoo's male giant panda, went well. But there is no way of telling whether Ming Ming is pregnant, or just thinks she is. Phantom pregnancies are common in giant pandas.
'I think Berlin is getting a bit over excited. We have no hard evidence,' he said.
Bao Bao's veterinary surgeon is reported to have said on a German television programme that 14-year-old Ming Ming is pregnant and expected to produce around the end of the year. Mr Carman said September is the most likely month for her to give birth. 'If we get beyond 1 October I will think this is a false alarm.'