Regarding the origin and oblivion of the N.N. Chukalov's method for extracting separated placenta

Today, understanding physiology of the placental period during normal childbirth, its management, identifying a moment of placental separation and methods for extracting separated and freely-lying birth canal placenta have been well documented. Nevertheless, the history of obstetrics and gynecology keeps everyday work secrets. Here, we would like to uncover one of them to the AGR readers primarily aimed at describing the "unknown" along with the "well-known" moment and restore "historical justice".