Without ultrasound, how do you know whether a fetus in utero is facing the right way? You use Leopold’s manoeuvres.
When a baby is being born their position in the womb is of utmost importance. Babies facing downwards come out head-first, and that’s the easiest and safest path. If the baby is pointing the wrong way, complications can quickly ensue. The so-called breech birth (butt-first) carries the risk of the umbilical cord getting squeezed and cutting off oxygen to the baby, or the head getting stuck coming out.
(Side note: I am reliably informed that, because the butt comes out before the legs in a breech birth, quite often the first part of a male baby to actually appear is the testes. Just poking out on their own. On an unrelated note, Frank Sinatra was a breech birth.)
Foreknowledge of the position of a fetus, then, is crucial to a successful birth. The 19th century German gynaecologist Christian Gerhard Leopold published a set of four simple manoeuvres that could determine which way it is facing while still in the womb.
Essentially, you feel around the parent’s belly looking for particular distinctive characteristics. In particular, you want to find the head, the feet, the spine, and the forehead.
Step one: press the top of the upper abdomen with your hands, looking for the head or the butt. Wiggle whatever you find back and forth: the head will move on its own, but if you wiggle the butt the rest of the baby’s torso will move accordingly. Plus the butt has legs sticking out, whereas the head has fewer legs sticking out.
Step two: press the middle abdomen, to identify which way the baby is facing. On one side should be the back and spine; on the other side are all the hands and feet.
Step three: press the lower abdomen, to confirm that step one was correctly read and that the other side is facing down (and, presumably, to confirm that the baby is not just two heads or two butts).
Step four: press the abdomen outside the head, to find the forehead. The intention is to see whether the forehead is opposite the back or not, I guess.
Anyway, this completely non-intrusive technique is still used today, although you can get a better read from an ultrasound.