After a long period of acceleration in the development of children bom in Goerlitz, GDR, there are now some changes in the direction of deceleration. The menarcheal age, for example, is rising. The evidence is convincing that the acceleration of sexual maturation has reached its culmination.
Richter, Joachim and Kern, Gottfried
"Secular Changes in the Development of Children Born in Goerlitz, German Democratic Republic, 1956 to 1967,"
2, Article 15.
Available at: https://digitalcommons.wayne.edu/humbiol/vol59/iss2/15