Going out on a limb here, but the only ways someone of that century could know the fetal position is to have had a very friendly and agreeable pregnant lady ... or he had an opportunit to see or be witness to an autopsy of a pregnant cadaver
DaVinchi studied medicine for several years in his youth.
Cadavers. I’m guessing that’s where all the sketches of muscle groups, organs, circulatory systems etc came from during those and later years, before modern medicine’s CAT/MRI techniques.
Leonardo regularly drew cadavers as a part of his study of the anatomy.
Although illegal at the time, it was not uncommon for artist and scientist to perform autopsies on the deceased poor.
Actually, in da Vinci's day, dissecting dead bodies was frowned upon and often conducted in secrecy. For medical students, there was the option of the anatomy theater. Picture a room crammed full of medical students. A smelly, decomposing corpse lies on a table as students in the amphitheaterlike room crane their necks to see it. One man begins to autopsy the corpse as another man, not necessarily within view of the body, reads from a classic anatomy text. As most of the students aren't even close enough to see them, the man doing the autopsy skips over nerves and other small structures. More importantly, it is the text that rules the day — both men teach to the text, whether or not it matches up with what they find in the actual body in front of them.
It is this disconnect that Leonardo da Vinci resolved to overcome. He would crack the code of the body in front of him — observing it, probing it, cutting into it, investigating it. He would study its inner structures to determine the body's most intricate inner functions. And he hoped that in doing so, he would find whatever it is that makes people truly alive: the soul.
The man was a revolutionary. Da Vinci's meticulous, detailed drawings of the human body were unlike anything anyone had ever seen. He sketched the skull from different angles after injecting the brain with hot wax to see its ventricles, used wires and threads attached to a skeleton's bones to understand human movement and heated a cow's eyeballs in egg yolks in order to section them.
Leonardo used cadavers in his anatomical studies.
Actually, he had clandestine access to the morgue - where he would, in the wee hours, dissect cadavers...which he did
I remember reading somewhere that Leonardo came up with hard boiling the eye so that it would withstand dissection.
And if a pregnant lady took ill or died by accident, could not her death, and her baby’s death, be given some meaning in this study?