Broadly based statistical studies into sexual behaviour are largely confined to the twentieth
century. If we stretch
the term sexological, however, we can find statistical studies as early as the sixteenth century.
François Rabelais
(c. 1490-1553) checked the monthly distribution of christenings in his part of France and
discovered a peak
incidence in October and November - leading him to the conclusion that the first thaws of
January and February
resulted in increased sexual activity. A later French researcher, Villermé, had reported
in 1831 on the basis of
17,000,000 births, that the maximum of French conceptions occur in April, May, and June.