With DD2 the sonographer pointed out there is "her" stomach. I didn't want to say anything out of fear it would be confirmed as we wanted a surprise so I didn't say anything. DH didn't think he was referring to bubz been a girl just saying that instead of it but she came out a DD and from that moment I had a strong feeling I was having a girl. My Aunt also was told she was having a boy when she didn't want to know with her first.
As a midwife I always refer to the bub inutero as a he or a she especially in labour when I don't know but I make sure to call it he and then she a few times so I don't favour one or the other IYKWIM. Much nicer to say he or she then it if you don't know.