Paré’s 13 Reasons for Teratogenesis
The first is the glory of God.
The second, His wrath.
The third, too great a quantity of semen.
The fourth, too small a quantity.
The fifth, imagination.
The sixth, the narrowness or smallness of the womb.
The seventh, the unbecoming sitting position of the mother, who, while pregnant, remains seated too long with her thighs crossed or pressed against her stomach.
The eighth, by a fall or blows struck against the stomach of the mother during pregnancy.
The ninth, by hereditary or accidental illnesses.
The tenth, by the rotting or corruption of the semen.
The eleventh, by the mingling or mixture of seed.
The twelfth, by the artifice of wandering beggars.
The thirteenth, by Demons or Devils.
The ones bolded above are particularly relevant to a discussion of maternal impression. Paré cites children born covered in dark hair (possibly hypertrichosis) as caused by the sight of something wild. He warns “truly I think it best to keep the woman all the time she goeth with child, from the sight and of such shapes and figures.”
Another story of maternal impression from Paré is that of a child born with the face of a frog in 1517. As Paré recounts, the child’s mother had come down with a serious illness resulting in fever. On the advice of a neighbor, she attempted a cure in which she should take a live frog and hold it in her hands until it died. That night, she went to bed still holding the frog and “her and her husband embraced and conceived; thus this monster you see in this picture (< Image Link) was born by virtue of her imagination.”
Paré's belief in maternal impression as a cause of monstrosity is of note due to the influence his writing on medicine had throughout the rest of the early modern period.