Kerri Walsh Jennings was unduly moody on her way to winning the women's beach volleyball competition last month, leading teammates to joke she was pregnant.
She was; a test on her return to the US confirmed the mother-of-two's suspicion that she had been with child (for five weeks).
The revelation comes after the more dramatic baby news from Afghanistan of Lynette Pearce's shock delivery after six months of un-noticed pregnancy, while fighting.
How much physical activity can one do with a bump? The NHS encourages exercise during pregnancy but advises against sport that involves breathlessness or falling (volleyball appears to be a bad idea) as well as, helpfully, kickboxing.
Early pregnancy has been shown to boost performance in athletes, due to increased red blood cell production, leading, bleakly, to rumours during the 1980s of "abortion doping" among East Germans.
Many other athletes have excelled while pregnant, including Anky van Grunsven (equestrian, 2004, five months pregnant) and, this year, Anna-Maria Johansson (handball, three months) and Nur Taibi (shooting, eight months).