Prime Minister Boris Johnson and his fiancee Carrie Symonds are celebrating the arrival of a healthy baby boy, but there has been speculation about whether he came early.
Ms Symonds’s due date, which was never officially confirmed, had been described as “early summer”, leading to the belief that the arrival was expected in June.
Ms Symonds, 32, revealed this month that she had been in self-isolation after suffering coronavirus symptoms.
The baby comes just weeks after Mr Johnson, 55, was treated in intensive care after testing positive for the virus.
Dr Sarah Stock, a senior clinical lecturer in maternal and fetal medicine at Edinburgh University, said: “Preterm birth is birth less than 37 weeks’ gestation.
“If Boris and Carrie’s baby was due in early June, then it has been born early.
“At the moment, we don’t know whether Covid-19 infection causes preterm labour or other pregnancy complications that can lead to early birth.”