The name and definition of hormonal reactions of pregnancy originated with Halban.1 His definition outlined the origin of two neonatal phenomena, namely, physiologic neonatal mastitis and physiologic neonatal vaginal bleeding.
The first phenomenon is well known: The mammae of the new-born child (each originally consists of ten to fifteen radially arranged mammae, the entire glandular mass being approximately 5 to 10 mm. in diameter) begin to grow on the third or fourth day after birth and on the fifth or sixth, more often on the eighth to the twelfth, surpass their original size many times; externally they appear swollen. A substance at first thin and watery, later yellowish and milky, like colostrum in composition (popularly called witches' milk), can be pressed from them. The swelling disappears within two to three weeks; it rarely lasts from one to two months. Vaginal bleeding of newborn infants is less frequent than the
DOBSZAY L. HORMONAL REACTIONS OF PREGNANCY. Am J Dis Child. 1938;56(6):1280–1293. doi:10.1001/archpedi.1938.01980180094008