I don't know how the 1965 photo was made, but he went on to take more later, apparently in connection with amniocentesis. [0]
> LN: Oh, yes. There has been a revolution by a German optical company called Storz. They have made an endoscope with a diameter of 0.6 millimeters and one that is 0.8 millimeters. So now we can check the human embryo in a very smooth and very nice way.
> NOVA: Do you go through the cervix?
> LN: No, not the cervix. We make a kind of laparoscopy through the uterine wall. You know when the doctors are checking the genes with amniocentesis? We have done a few cases here in Sweden and in Europe during amniocentesis. And there we had the opportunity to take wonderful pictures of the fetuses.
I guess during laparoscopic surgery you typically insert a camera anyway, so maybe taking some additional photos doesn't add so much risk.