Flinging sperm out

“To fling sperm out of the vagina is common in Hungary and Austria. Straightening up immediately after intercourse the woman spreads her legs and through wiggling movements of her body tries to throw male sperm out with a forceful flip.”
This interesting "method of contraception" was recounted by Saxonian health reformer and promoter of natural medicine Friedrich Eduard Bilz (1842-1922) in his book "The new naturopathic treatment – a textbook and reference book of natural treatment and healthcare" (‘Das neue Naturheilverfahren – Lehr- und Nachschlagebuch der naturgemäßen Heilweise und Gesundheitspflege’) from around 1900.

Even Berlin’s "Father of Sexology" Iwan Bloch (1872-1922) had heard about this technique, but in his book "Sexual life of our time in relation to modern culture" (‘Das Sexualleben unserer Zeit in seinen Beziehungen zur modernen Kultur’) he placed its origin somewhere else: "In Italy and New-Guinea some women remove the sperm from their vagina post coitus using the action of their muscles together with powerful body movements.“
Unnecessary to say that living in Vienna ourselves, we never heart about this method.